1 What has changed since GDB-3.5?
2 (Organized release by release)
4 *** Changes in GDB-???:
6 * User visible changes:
8 Remote debugging using the GDB-specific (`target remote') protocol now
9 supports the `load' command. This is only useful if you have some
10 other way of getting the stub to the target system, and you can put it
11 somewhere in memory where it won't get clobbered by the download.
13 Filename completion now works.
15 When run under emacs mode, the "info line" command now causes the
16 arrow to point to the line specified. Also, "info line" prints
17 addresses in symbolic form (as well as hex).
19 All vxworks based targets now support a user settable option, called
20 vxworks-timeout. This option represents the number of seconds gdb
21 should wait for responses to rpc's. You might want to use this if
22 your vxworks target is, perhaps, a slow software simulator or happens
23 to be on the far side of a thin network line.
27 This release contains support for using a DEC alpha as a GDB host for
28 cross debugging. Native alpha debugging is not supported yet.
31 *** Changes in GDB-4.9:
35 This is the first GDB release which is accompanied by a matching testsuite.
36 The testsuite requires installation of dejagnu, which should be available
37 via ftp from most sites that carry GNU software.
41 'Cfront' style demangling has had its name changed to 'ARM' style, to
42 emphasize that it was written from the specifications in the C++ Annotated
43 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
44 disclaimers, it still generated too much confusion with users attempting to
45 use gdb with AT&T cfront.
49 GDB now uses a standard remote interface to a simulator library.
50 So far, the library contains simulators for the Zilog Z8001/2, the
51 Hitachi H8/300, H8/500 and Super-H.
53 * New targets supported
55 H8/300 simulator h8300-hitachi-hms or h8300hms
56 H8/500 simulator h8500-hitachi-hms or h8500hms
57 SH simulator sh-hitachi-hms or sh
58 Z8000 simulator z8k-zilog-none or z8ksim
59 IDT MIPS board over serial line mips-idt-ecoff
61 Cross-debugging to GO32 targets is supported. It requires a custom
62 version of the i386-stub.c module which is integrated with the
65 * New remote protocols
67 MIPS remote debugging protocol.
69 * New source languages supported
71 This version includes preliminary support for Chill, a Pascal like language
72 used by telecommunications companies. Chill support is also being integrated
73 into the GNU compiler, but we don't know when it will be publically available.
76 *** Changes in GDB-4.8:
78 * HP Precision Architecture supported
80 GDB now supports HP PA-RISC machines running HPUX. A preliminary
81 version of this support was available as a set of patches from the
82 University of Utah. GDB does not support debugging of programs
83 compiled with the HP compiler, because HP will not document their file
84 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
85 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
87 Many problems in the preliminary version have been fixed.
89 * Faster and better demangling
91 We have improved template demangling and fixed numerous bugs in the GNU style
92 demangler. It can now handle type modifiers such as `static' or `const'. Wide
93 character types (wchar_t) are now supported. Demangling of each symbol is now
94 only done once, and is cached when the symbol table for a file is read in.
95 This results in a small increase in memory usage for C programs, a moderate
96 increase in memory usage for C++ programs, and a fantastic speedup in
99 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
100 from the specifications in the Annotated Reference Manual, which AT&T's
101 compiler does not actually implement.
103 * G++ multiple inheritance compiler problem
105 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
106 inheritance lattices was reworked to properly discover ambiguities. We
107 recently found an example which causes this new algorithm to fail in a
108 very subtle way, producing bad debug information for those classes.
109 The file 'gcc.patch' (in this directory) can be applied to gcc to
110 circumvent the problem. A future GCC release will contain a complete
113 The previous G++ debug info problem (mentioned below for the gdb-4.7
114 release) is fixed in gcc version 2.3.2.
116 * Improved configure script
118 The `configure' script will now attempt to guess your system type if
119 you don't supply a host system type. The old scheme of supplying a
120 host system triplet is preferable over using this. All the magic is
121 done in the new `config.guess' script. Examine it for details.
123 We have also brought our configure script much more in line with the FSF's
124 version. It now supports the --with-xxx options. In particular,
125 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
126 The resulting GDB will not be able to read arbitrary object file formats --
127 only the format ``expected'' to be used on the configured target system.
128 We hope to make this the default in a future release.
130 * Documentation improvements
132 There's new internal documentation on how to modify GDB, and how to
133 produce clean changes to the code. We implore people to read it
134 before submitting changes.
136 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
137 M4 macros. The new texinfo.tex is provided in this release. Pre-built
138 `info' files are also provided. To build `info' files from scratch,
139 you will need the latest `makeinfo' release, which will be available in
140 a future texinfo-X.Y release.
142 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
143 We're not sure exactly which versions have this problem, but it has
144 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
145 or better. If that isn't possible, there is a patch in
146 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
151 GDB now supports array constants that can be used in expressions typed in by
152 the user. The syntax is `{element, element, ...}'. Ie: you can now type
153 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
156 The new directory `gdb/sparclite' contains a program that demonstrates
157 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
159 * New native hosts supported
161 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
162 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
164 * New targets supported
166 AMD 29k family via UDI a29k-amd-udi or udi29k
168 * New file formats supported
170 BFD now supports reading HP/PA-RISC executables (SOM file format?),
171 HPUX core files, and SCO 3.2v2 core files.
175 Attaching to processes now works again; thanks for the many bug reports.
177 We have also stomped on a bunch of core dumps caused by
178 printf_filtered("%s") problems.
180 We eliminated a copyright problem on the rpc and ptrace header files
181 for VxWorks, which was discovered at the last minute during the 4.7
182 release. You should now be able to build a VxWorks GDB.
184 You can now interrupt gdb while an attached process is running. This
185 will cause the attached process to stop, and give control back to GDB.
187 We fixed problems caused by using too many file descriptors
188 for reading symbols from object files and libraries. This was
189 especially a problem for programs that used many (~100) shared
192 The `step' command now only enters a subroutine if there is line number
193 information for the subroutine. Otherwise it acts like the `next'
194 command. Previously, `step' would enter subroutines if there was
195 any debugging information about the routine. This avoids problems
196 when using `cc -g1' on MIPS machines.
198 * Internal improvements
200 GDB's internal interfaces have been improved to make it easier to support
201 debugging of multiple languages in the future.
203 GDB now uses a common structure for symbol information internally.
204 Minimal symbols (derived from linkage symbols in object files), partial
205 symbols (from a quick scan of debug information), and full symbols
206 contain a common subset of information, making it easier to write
207 shared code that handles any of them.
209 * New command line options
211 We now accept --silent as an alias for --quiet.
215 The memory-mapped-malloc library is now licensed under the GNU Library
216 General Public License.
218 *** Changes in GDB-4.7:
220 * Host/native/target split
222 GDB has had some major internal surgery to untangle the support for
223 hosts and remote targets. Now, when you configure GDB for a remote
224 target, it will no longer load in all of the support for debugging
225 local programs on the host. When fully completed and tested, this will
226 ensure that arbitrary host/target combinations are possible.
228 The primary conceptual shift is to separate the non-portable code in
229 GDB into three categories. Host specific code is required any time GDB
230 is compiled on that host, regardless of the target. Target specific
231 code relates to the peculiarities of the target, but can be compiled on
232 any host. Native specific code is everything else: it can only be
233 built when the host and target are the same system. Child process
234 handling and core file support are two common `native' examples.
236 GDB's use of /proc for controlling Unix child processes is now cleaner.
237 It has been split out into a single module under the `target_ops' vector,
238 plus two native-dependent functions for each system that uses /proc.
240 * New hosts supported
242 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
243 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
244 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
246 * New targets supported
248 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
249 68030 and CPU32 m68030-*-*, m68332-*-*
251 * New native hosts supported
253 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
254 (386bsd is not well tested yet)
255 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
257 * New file formats supported
259 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
260 supports reading of `a.out.adobe' object files, which are an a.out
261 format extended with minimal information about multiple sections.
265 `show copying' is the same as the old `info copying'.
266 `show warranty' is the same as `info warrantee'.
267 These were renamed for consistency. The old commands continue to work.
269 `info handle' is a new alias for `info signals'.
271 You can now define pre-command hooks, which attach arbitrary command
272 scripts to any command. The commands in the hook will be executed
273 prior to the user's command. You can also create a hook which will be
274 executed whenever the program stops. See gdb.texinfo.
278 We now deal with Cfront style name mangling, and can even extract type
279 info from mangled symbols. GDB can automatically figure out which
280 symbol mangling style your C++ compiler uses.
282 Calling of methods and virtual functions has been improved as well.
286 The crash that occured when debugging Sun Ansi-C compiled binaries is
287 fixed. This was due to mishandling of the extra N_SO stabs output
290 We also finally got Ultrix 4.2 running in house, and fixed core file
291 support, with help from a dozen people on the net.
293 John M. Farrell discovered that the reason that single-stepping was so
294 slow on all of the Mips based platforms (primarily SGI and DEC) was
295 that we were trying to demangle and lookup a symbol used for internal
296 purposes on every instruction that was being stepped through. Changing
297 the name of that symbol so that it couldn't be mistaken for a C++
298 mangled symbol sped things up a great deal.
300 Rich Pixley sped up symbol lookups in general by getting much smarter
301 about when C++ symbol mangling is necessary. This should make symbol
302 completion (TAB on the command line) much faster. It's not as fast as
303 we'd like, but it's significantly faster than gdb-4.6.
307 A new user controllable variable 'call_scratch_address' can
308 specify the location of a scratch area to be used when GDB
309 calls a function in the target. This is necessary because the
310 usual method of putting the scratch area on the stack does not work
311 in systems that have separate instruction and data spaces.
313 We integrated changes to support the 29k UDI (Universal Debugger
314 Interface), but discovered at the last minute that we didn't have all
315 of the appropriate copyright paperwork. We are working with AMD to
316 resolve this, and hope to have it available soon.
320 We have sped up the remote serial line protocol, especially for targets
321 with lots of registers. It now supports a new `expedited status' ('T')
322 message which can be used in place of the existing 'S' status message.
323 This allows the remote stub to send only the registers that GDB
324 needs to make a quick decision about single-stepping or conditional
325 breakpoints, eliminating the need to fetch the entire register set for
326 each instruction being stepped through.
328 The GDB remote serial protocol now implements a write-through cache for
329 registers, only re-reading the registers if the target has run.
331 There is also a new remote serial stub for SPARC processors. You can
332 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
333 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
334 processor with a serial port.
338 Configure.in files have become much easier to read and modify. A new
339 `table driven' format makes it more obvious what configurations are
340 supported, and what files each one uses.
344 There is a new opcodes library which will eventually contain all of the
345 disassembly routines and opcode tables. At present, it only contains
346 Sparc and Z8000 routines. This will allow the assembler, debugger, and
347 disassembler (binutils/objdump) to share these routines.
349 The libiberty library is now copylefted under the GNU Library General
350 Public License. This allows more liberal use, and was done so libg++
351 can use it. This makes no difference to GDB, since the Library License
352 grants all the rights from the General Public License.
356 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
357 reference to the stabs symbol info used by the debugger. It is (as far
358 as we know) the only published document on this fascinating topic. We
359 encourage you to read it, compare it to the stabs information on your
360 system, and send improvements on the document in general (to
361 bug-gdb@prep.ai.mit.edu).
363 And, of course, many bugs have been fixed.
366 *** Changes in GDB-4.6:
368 * Better support for C++ function names
370 GDB now accepts as input the "demangled form" of C++ overloaded function
371 names and member function names, and can do command completion on such names
372 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
373 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
374 Make use of command completion, it is your friend.
376 GDB also now accepts a variety of C++ mangled symbol formats. They are
377 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
378 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
379 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
380 for the list of formats.
382 * G++ symbol mangling problem
384 Recent versions of gcc have a bug in how they emit debugging information for
385 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
386 directory) can be applied to gcc to fix the problem. Alternatively, if you
387 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
388 usual symptom is difficulty with setting breakpoints on methods. GDB complains
389 about the method being non-existent. (We believe that version 2.2.2 of GCC has
392 * New 'maintenance' command
394 All of the commands related to hacking GDB internals have been moved out of
395 the main command set, and now live behind the 'maintenance' command. This
396 can also be abbreviated as 'mt'. The following changes were made:
398 dump-me -> maintenance dump-me
399 info all-breakpoints -> maintenance info breakpoints
400 printmsyms -> maintenance print msyms
401 printobjfiles -> maintenance print objfiles
402 printpsyms -> maintenance print psymbols
403 printsyms -> maintenance print symbols
405 The following commands are new:
407 maintenance demangle Call internal GDB demangler routine to
408 demangle a C++ link name and prints the result.
409 maintenance print type Print a type chain for a given symbol
411 * Change to .gdbinit file processing
413 We now read the $HOME/.gdbinit file before processing the argv arguments
414 (e.g. reading symbol files or core files). This allows global parameters to
415 be set, which will apply during the symbol reading. The ./.gdbinit is still
416 read after argv processing.
418 * New hosts supported
420 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
422 Linux support i386-unknown-linux or linux
424 We are also including code to support the HP/PA running BSD and HPUX. This
425 is almost guaranteed not to work, as we didn't have time to test or build it
426 for this release. We are including it so that the more adventurous (or
427 masochistic) of you can play with it. We also had major problems with the
428 fact that the compiler that we got from HP doesn't support the -g option.
431 * New targets supported
433 Hitachi H8/300 h8300-hitachi-hms or h8300hms
435 * More smarts about finding #include files
437 GDB now remembers the compilation directory for all include files, and for
438 all files from which C is generated (like yacc and lex sources). This
439 greatly improves GDB's ability to find yacc/lex sources, and include files,
440 especially if you are debugging your program from a directory different from
441 the one that contains your sources.
443 We also fixed a bug which caused difficulty with listing and setting
444 breakpoints in include files which contain C code. (In the past, you had to
445 try twice in order to list an include file that you hadn't looked at before.)
447 * Interesting infernals change
449 GDB now deals with arbitrary numbers of sections, where the symbols for each
450 section must be relocated relative to that section's landing place in the
451 target's address space. This work was needed to support ELF with embedded
452 stabs used by Solaris-2.0.
454 * Bug fixes (of course!)
456 There have been loads of fixes for the following things:
457 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
458 i960, stabs, DOS(GO32), procfs, etc...
460 See the ChangeLog for details.
462 *** Changes in GDB-4.5:
464 * New machines supported (host and target)
466 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
468 SGI Irix-4.x mips-sgi-irix4 or iris4
472 GDB now uses a new memory manager called mmalloc, based on gmalloc.
473 Mmalloc is capable of handling mutiple heaps of memory. It is also
474 capable of saving a heap to a file, and then mapping it back in later.
475 This can be used to greatly speedup the startup of GDB by using a
476 pre-parsed symbol table which lives in a mmalloc managed heap. For
477 more details, please read mmalloc/mmalloc.texi.
481 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
482 'help info proc' for details.
484 * MIPS ecoff symbol table format
486 The code that reads MIPS symbol table format is now supported on all hosts.
487 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
490 * File name changes for MS-DOS
492 Many files in the config directories have been renamed to make it easier to
493 support GDB on MS-DOSe systems (which have very restrictive file name
494 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
495 environment) is close to working but has some remaining problems. Note
496 that debugging of DOS programs is not supported, due to limitations
497 in the ``operating system'', but it can be used to host cross-debugging.
499 * Cross byte order fixes
501 Many fixes have been made to support cross debugging of Sparc and MIPS
502 targets from hosts whose byte order differs.
504 * New -mapped and -readnow options
506 If memory-mapped files are available on your system through the 'mmap'
507 system call, you can use the -mapped option on the `file' or
508 `symbol-file' commands to cause GDB to write the symbols from your
509 program into a reusable file. If the program you are debugging is
510 called `/path/fred', the mapped symbol file will be `./fred.syms'.
511 Future GDB debugging sessions will notice the presence of this file,
512 and will quickly map in symbol information from it, rather than reading
513 the symbol table from the executable program. Using the '-mapped'
514 option in a GDB `file' or `symbol-file' command has the same effect as
515 starting GDB with the '-mapped' command-line option.
517 You can cause GDB to read the entire symbol table immediately by using
518 the '-readnow' option with any of the commands that load symbol table
519 information (or on the GDB command line). This makes the command
520 slower, but makes future operations faster.
522 The -mapped and -readnow options are typically combined in order to
523 build a `fred.syms' file that contains complete symbol information.
524 A simple GDB invocation to do nothing but build a `.syms' file for future
527 gdb -batch -nx -mapped -readnow programname
529 The `.syms' file is specific to the host machine on which GDB is run.
530 It holds an exact image of GDB's internal symbol table. It cannot be
531 shared across multiple host platforms.
535 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
536 siglongjmp() without losing control. This feature has not yet been ported to
537 all systems. It currently works on many 386 platforms, all MIPS-based
538 platforms (SGI, DECstation, etc), and Sun3/4.
542 Preliminary work has been put in to support the new Solaris OS from Sun. At
543 this time, it can control and debug processes, but it is not capable of
548 As always, many many bug fixes. The major areas were with g++, and mipsread.
549 People using the MIPS-based platforms should experience fewer mysterious
550 crashes and trashed symbol tables.
552 *** Changes in GDB-4.4:
554 * New machines supported (host and target)
556 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
558 BSD Reno on Vax vax-dec-bsd
559 Ultrix on Vax vax-dec-ultrix
561 * New machines supported (target)
563 AMD 29000 embedded, using EBMON a29k-none-none
567 GDB continues to improve its handling of C++. `References' work better.
568 The demangler has also been improved, and now deals with symbols mangled as
569 per the Annotated C++ Reference Guide.
571 GDB also now handles `stabs' symbol information embedded in MIPS
572 `ecoff' symbol tables. Since the ecoff format was not easily
573 extensible to handle new languages such as C++, this appeared to be a
574 good way to put C++ debugging info into MIPS binaries. This option
575 will be supported in the GNU C compiler, version 2, when it is
578 * New features for SVR4
580 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
581 shared libraries. Debugging dynamically linked programs should present
582 only minor differences from debugging statically linked programs.
584 The `info proc' command will print out information about any process
585 on an SVR4 system (including the one you are debugging). At the moment,
586 it prints the address mappings of the process.
588 If you bring up GDB on another SVR4 system, please send mail to
589 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
591 * Better dynamic linking support in SunOS
593 Reading symbols from shared libraries which contain debugging symbols
594 now works properly. However, there remain issues such as automatic
595 skipping of `transfer vector' code during function calls, which
596 make it harder to debug code in a shared library, than to debug the
597 same code linked statically.
601 GDB is now using the latest `getopt' routines from the FSF. This
602 version accepts the -- prefix for options with long names. GDB will
603 continue to accept the old forms (-option and +option) as well.
604 Various single letter abbreviations for options have been explicity
605 added to the option table so that they won't get overshadowed in the
606 future by other options that begin with the same letter.
610 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
611 Many assorted bugs have been handled. Many more remain to be handled.
612 See the various ChangeLog files (primarily in gdb and bfd) for details.
615 *** Changes in GDB-4.3:
617 * New machines supported (host and target)
619 Amiga 3000 running Amix m68k-cbm-svr4 or amix
620 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
621 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
623 * Almost SCO Unix support
625 We had hoped to support:
626 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
627 (except for core file support), but we discovered very late in the release
628 that it has problems with process groups that render gdb unusable. Sorry
629 about that. I encourage people to fix it and post the fixes.
631 * Preliminary ELF and DWARF support
633 GDB can read ELF object files on System V Release 4, and can handle
634 debugging records for C, in DWARF format, in ELF files. This support
635 is preliminary. If you bring up GDB on another SVR4 system, please
636 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
641 GDB now uses the latest `readline' library. One user-visible change
642 is that two tabs will list possible command completions, which previously
643 required typing M-? (meta-question mark, or ESC ?).
647 The `stepi' bug that many of you noticed has been squashed.
648 Many bugs in C++ have been handled. Many more remain to be handled.
649 See the various ChangeLog files (primarily in gdb and bfd) for details.
651 * State of the MIPS world (in case you wondered):
653 GDB can understand the symbol tables emitted by the compilers
654 supplied by most vendors of MIPS-based machines, including DEC. These
655 symbol tables are in a format that essentially nobody else uses.
657 Some versions of gcc come with an assembler post-processor called
658 mips-tfile. This program is required if you want to do source-level
659 debugging of gcc-compiled programs. I believe FSF does not ship
660 mips-tfile with gcc version 1, but it will eventually come with gcc
663 Debugging of g++ output remains a problem. g++ version 1.xx does not
664 really support it at all. (If you're lucky, you should be able to get
665 line numbers and stack traces to work, but no parameters or local
666 variables.) With some work it should be possible to improve the
669 When gcc version 2 is released, you will have somewhat better luck.
670 However, even then you will get confusing results for inheritance and
673 We will eventually provide full debugging of g++ output on
674 DECstations. This will probably involve some kind of stabs-in-ecoff
675 encapulation, but the details have not been worked out yet.
678 *** Changes in GDB-4.2:
680 * Improved configuration
682 Only one copy of `configure' exists now, and it is not self-modifying.
683 Porting BFD is simpler.
687 The `step' and `next' commands now only stop at the first instruction
688 of a source line. This prevents the multiple stops that used to occur
689 in switch statements, for-loops, etc. `Step' continues to stop if a
690 function that has debugging information is called within the line.
694 Lots of small bugs fixed. More remain.
696 * New host supported (not target)
698 Intel 386 PC clone running Mach i386-none-mach
701 *** Changes in GDB-4.1:
703 * Multiple source language support
705 GDB now has internal scaffolding to handle several source languages.
706 It determines the type of each source file from its filename extension,
707 and will switch expression parsing and number formatting to match the
708 language of the function in the currently selected stack frame.
709 You can also specifically set the language to be used, with
710 `set language c' or `set language modula-2'.
714 GDB now has preliminary support for the GNU Modula-2 compiler,
715 currently under development at the State University of New York at
716 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
717 continue through the fall of 1991 and into 1992.
719 Other Modula-2 compilers are currently not supported, and attempting to
720 debug programs compiled with them will likely result in an error as the
721 symbol table is read. Feel free to work on it, though!
723 There are hooks in GDB for strict type checking and range checking,
724 in the `Modula-2 philosophy', but they do not currently work.
728 GDB can now write to executable and core files (e.g. patch
729 a variable's value). You must turn this switch on, specify
730 the file ("exec foo" or "core foo"), *then* modify it, e.g.
731 by assigning a new value to a variable. Modifications take
734 * Automatic SunOS shared library reading
736 When you run your program, GDB automatically determines where its
737 shared libraries (if any) have been loaded, and reads their symbols.
738 The `share' command is no longer needed. This also works when
739 examining core files.
743 You can specify the number of lines that the `list' command shows.
746 * New machines supported (host and target)
748 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
749 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
750 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
752 * New hosts supported (not targets)
754 IBM RT/PC: romp-ibm-aix or rtpc
756 * New targets supported (not hosts)
758 AMD 29000 embedded with COFF a29k-none-coff
759 AMD 29000 embedded with a.out a29k-none-aout
760 Ultracomputer remote kernel debug a29k-nyu-kern
762 * New remote interfaces
768 *** Changes in GDB-4.0:
772 Wide output is wrapped at good places to make the output more readable.
774 Gdb now supports cross-debugging from a host machine of one type to a
775 target machine of another type. Communication with the target system
776 is over serial lines. The ``target'' command handles connecting to the
777 remote system; the ``load'' command will download a program into the
778 remote system. Serial stubs for the m68k and i386 are provided. Gdb
779 also supports debugging of realtime processes running under VxWorks,
780 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
781 stub on the target system.
783 New CPUs supported include the AMD 29000 and Intel 960.
785 GDB now reads object files and symbol tables via a ``binary file''
786 library, which allows a single copy of GDB to debug programs of multiple
787 object file types such as a.out and coff.
789 There is now a GDB reference card in "doc/refcard.tex". (Make targets
790 refcard.dvi and refcard.ps are available to format it).
793 * Control-Variable user interface simplified
795 All variables that control the operation of the debugger can be set
796 by the ``set'' command, and displayed by the ``show'' command.
798 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
799 ``Show prompt'' produces the response:
800 Gdb's prompt is new-gdb=>.
802 What follows are the NEW set commands. The command ``help set'' will
803 print a complete list of old and new set commands. ``help set FOO''
804 will give a longer description of the variable FOO. ``show'' will show
805 all of the variable descriptions and their current settings.
807 confirm on/off: Enables warning questions for operations that are
808 hard to recover from, e.g. rerunning the program while
809 it is already running. Default is ON.
811 editing on/off: Enables EMACS style command line editing
812 of input. Previous lines can be recalled with
813 control-P, the current line can be edited with control-B,
814 you can search for commands with control-R, etc.
817 history filename NAME: NAME is where the gdb command history
818 will be stored. The default is .gdb_history,
819 or the value of the environment variable
822 history size N: The size, in commands, of the command history. The
823 default is 256, or the value of the environment variable
826 history save on/off: If this value is set to ON, the history file will
827 be saved after exiting gdb. If set to OFF, the
828 file will not be saved. The default is OFF.
830 history expansion on/off: If this value is set to ON, then csh-like
831 history expansion will be performed on
832 command line input. The default is OFF.
834 radix N: Sets the default radix for input and output. It can be set
835 to 8, 10, or 16. Note that the argument to "radix" is interpreted
836 in the current radix, so "set radix 10" is always a no-op.
838 height N: This integer value is the number of lines on a page. Default
839 is 24, the current `stty rows'' setting, or the ``li#''
840 setting from the termcap entry matching the environment
843 width N: This integer value is the number of characters on a line.
844 Default is 80, the current `stty cols'' setting, or the ``co#''
845 setting from the termcap entry matching the environment
848 Note: ``set screensize'' is obsolete. Use ``set height'' and
849 ``set width'' instead.
851 print address on/off: Print memory addresses in various command displays,
852 such as stack traces and structure values. Gdb looks
853 more ``symbolic'' if you turn this off; it looks more
854 ``machine level'' with it on. Default is ON.
856 print array on/off: Prettyprint arrays. New convenient format! Default
859 print demangle on/off: Print C++ symbols in "source" form if on,
862 print asm-demangle on/off: Same, for assembler level printouts
865 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
868 * Support for Epoch Environment.
870 The epoch environment is a version of Emacs v18 with windowing. One
871 new command, ``inspect'', is identical to ``print'', except that if you
872 are running in the epoch environment, the value is printed in its own
876 * Support for Shared Libraries
878 GDB can now debug programs and core files that use SunOS shared libraries.
879 Symbols from a shared library cannot be referenced
880 before the shared library has been linked with the program (this
881 happens after you type ``run'' and before the function main() is entered).
882 At any time after this linking (including when examining core files
883 from dynamically linked programs), gdb reads the symbols from each
884 shared library when you type the ``sharedlibrary'' command.
885 It can be abbreviated ``share''.
887 sharedlibrary REGEXP: Load shared object library symbols for files
888 matching a unix regular expression. No argument
889 indicates to load symbols for all shared libraries.
891 info sharedlibrary: Status of loaded shared libraries.
896 A watchpoint stops execution of a program whenever the value of an
897 expression changes. Checking for this slows down execution
898 tremendously whenever you are in the scope of the expression, but is
899 quite useful for catching tough ``bit-spreader'' or pointer misuse
900 problems. Some machines such as the 386 have hardware for doing this
901 more quickly, and future versions of gdb will use this hardware.
903 watch EXP: Set a watchpoint (breakpoint) for an expression.
905 info watchpoints: Information about your watchpoints.
907 delete N: Deletes watchpoint number N (same as breakpoints).
908 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
909 enable N: Re-enables watchpoint number N (same as breakpoints).
912 * C++ multiple inheritance
914 When used with a GCC version 2 compiler, GDB supports multiple inheritance
917 * C++ exception handling
919 Gdb now supports limited C++ exception handling. Besides the existing
920 ability to breakpoint on an exception handler, gdb can breakpoint on
921 the raising of an exception (before the stack is peeled back to the
924 catch FOO: If there is a FOO exception handler in the dynamic scope,
925 set a breakpoint to catch exceptions which may be raised there.
926 Multiple exceptions (``catch foo bar baz'') may be caught.
928 info catch: Lists all exceptions which may be caught in the
932 * Minor command changes
934 The command ``call func (arg, arg, ...)'' now acts like the print
935 command, except it does not print or save a value if the function's result
936 is void. This is similar to dbx usage.
938 The ``up'' and ``down'' commands now always print the frame they end up
939 at; ``up-silently'' and `down-silently'' can be used in scripts to change
940 frames without printing.
942 * New directory command
944 'dir' now adds directories to the FRONT of the source search path.
945 The path starts off empty. Source files that contain debug information
946 about the directory in which they were compiled can be found even
947 with an empty path; Sun CC and GCC include this information. If GDB can't
948 find your source file in the current directory, type "dir .".
950 * Configuring GDB for compilation
952 For normal use, type ``./configure host''. See README or gdb.texinfo
955 GDB now handles cross debugging. If you are remotely debugging between
956 two different machines, type ``./configure host -target=targ''.
957 Host is the machine where GDB will run; targ is the machine
958 where the program that you are debugging will run.
projects / platform / upstream / binutils.git / blob