1 README for gdb-5.0 release
2 Updated 11 May 2000 by Andrew Cagney
4 This is GDB, the GNU source-level debugger.
5 A summary of new features is in the file `NEWS'.
7 See the GDB home page at http://sourceware.cygnus.com/gdb/ for up to
8 date release information, mailing list links and archives, etc.
11 Unpacking and Installation -- quick overview
12 ==========================
14 In this release, the GDB debugger sources, the generic GNU include
15 files, the BFD ("binary file description") library, the readline
16 library, and other libraries all have directories of their own
17 underneath the gdb-5.0 directory. The idea is that a variety of GNU
18 tools can share a common copy of these things. Be aware of variation
19 over time--for example don't try to build gdb with a copy of bfd from
20 a release other than the gdb release (such as a binutils or gas
21 release), especially if the releases are more than a few weeks apart.
22 Configuration scripts and makefiles exist to cruise up and down this
23 directory tree and automatically build all the pieces in the right
26 When you unpack the gdb-5.0.tar.gz file, you'll find a directory
27 called `gdb-5.0', which contains:
29 COPYING config.if install-sh mmalloc readline
30 COPYING.LIB config.sub intl move-if-change sim
31 Makefile.in configure libiberty mpw-README symlink-tree
32 README configure.in ltconfig mpw-build.in texinfo
33 bfd djunpack.bat ltmain.sh mpw-config.in utils
34 config etc md5.sum mpw-configure ylwrap
35 config-ml.in gdb missing mpw-install
36 config.guess include mkinstalldirs opcodes
38 To build GDB, you can just do:
43 cp gdb/gdb /usr/local/bin/gdb (or wherever you want)
45 (Building GDB with DJGPP tools for MS-DOS/MS-Windows is slightly
46 different; see the file gdb-5.0/gdb/config/djgpp/README for details.)
48 This will configure and build all the libraries as well as GDB. If
49 `configure' can't determine your system type, specify one as its
50 argument, e.g., `./configure sun4' or `./configure decstation'.
52 If you get compiler errors during this stage, see the `Reporting
53 Bugs' section below; there are a few known problems.
55 GDB requires an ISO-C (ANSI C) compiler. If you do not have an
56 ISO-C compiler for your system, you may be able to download and
57 install the GNU CC compiler. It is available via anonymous FTP from
58 the directory `ftp://ftp.gnu.org/pub/gnu/gcc'.
60 GDB can be used as a cross-debugger, running on a machine of one
61 type while debugging a program running on a machine of another type.
68 All the documentation for GDB comes as part of the machine-readable
69 distribution. The documentation is written in Texinfo format, which
70 is a documentation system that uses a single source file to produce
71 both on-line information and a printed manual. You can use one of the
72 Info formatting commands to create the on-line version of the
73 documentation and TeX (or `texi2roff') to typeset the printed version.
75 GDB includes an already formatted copy of the on-line Info version
76 of this manual in the `gdb/doc' subdirectory. The main Info file is
77 `gdb-5.0/gdb/doc/gdb.info', and it refers to subordinate files
78 matching `gdb.info*' in the same directory. If necessary, you can
79 print out these files, or read them with any editor; but they are
80 easier to read using the `info' subsystem in GNU Emacs or the
81 standalone `info' program, available as part of the GNU Texinfo
84 If you want to format these Info files yourself, you need one of the
85 Info formatting programs, such as `texinfo-format-buffer' or
88 If you have `makeinfo' installed, and are in the top level GDB
89 source directory (`gdb-5.0', in the case of version 5.0), you can make
90 the Info file by typing:
95 If you want to typeset and print copies of this manual, you need
96 TeX, a program to print its DVI output files, and `texinfo.tex', the
97 Texinfo definitions file. This file is included in the GDB
98 distribution, in the directory `gdb-5.0/texinfo'.
100 TeX is a typesetting program; it does not print files directly, but
101 produces output files called DVI files. To print a typeset document,
102 you need a program to print DVI files. If your system has TeX
103 installed, chances are it has such a program. The precise command to
104 use depends on your system; `lpr -d' is common; another (for PostScript
105 devices) is `dvips'. The DVI print command may require a file name
106 without any extension or a `.dvi' extension.
108 TeX also requires a macro definitions file called `texinfo.tex'.
109 This file tells TeX how to typeset a document written in Texinfo
110 format. On its own, TeX cannot read, much less typeset a Texinfo file.
111 `texinfo.tex' is distributed with GDB and is located in the
112 `gdb-5.0/texinfo' directory.
114 If you have TeX and a DVI printer program installed, you can typeset
115 and print this manual. First switch to the the `gdb' subdirectory of
116 the main source directory (for example, to `gdb-5.0/gdb') and then type:
124 GDB comes with a `configure' script that automates the process of
125 preparing GDB for installation; you can then use `make' to build the
128 The GDB distribution includes all the source code you need for GDB in
129 a single directory, whose name is usually composed by appending the
130 version number to `gdb'.
132 For example, the GDB version 5.0 distribution is in the `gdb-5.0'
133 directory. That directory contains:
135 `gdb-5.0/{COPYING,COPYING.LIB}'
136 Standard GNU license files. Please read them.
139 source for the Binary File Descriptor library
142 script for configuring GDB, along with other support files
145 the source specific to GDB itself
151 source for the `-liberty' free software library
154 source for the GNU memory-mapped malloc package
157 source for the library of opcode tables and disassemblers
160 source for the GNU command-line interface
161 NOTE: The readline library is compiled for use by GDB, but will
162 not be installed on your system when "make install" is issued.
165 source for some simulators (ARM, D10V, SPARC, M32R, MIPS, PPC, V850, etc)
168 source for the GNU gettext library, for internationalization.
169 This is slightly modified from the standalone gettext
170 distribution you can get from GNU.
173 The `texinfo.tex' file, which you need in order to make a printed
177 Coding standards, useful files for editing GDB, and other
181 A grab bag of random utilities.
183 Note: the following instructions are for building GDB on Unix or
184 Unix-like systems. Instructions for building with DJGPP for
185 MS-DOS/MS-Windows are in the file gdb/config/djgpp/README.
187 The simplest way to configure and build GDB is to run `configure'
188 from the `gdb-VERSION-NUMBER' source directory, which in this example
189 is the `gdb-5.0' directory.
191 First switch to the `gdb-VERSION-NUMBER' source directory if you are
192 not already in it; then run `configure'.
200 Running `configure' followed by `make' builds the `bfd',
201 `readline', `mmalloc', and `libiberty' libraries, then `gdb' itself.
202 The configured source files, and the binaries, are left in the
203 corresponding source directories.
205 `configure' is a Bourne-shell (`/bin/sh') script; if your system
206 does not recognize this automatically when you run a different shell,
207 you may need to run `sh' on it explicitly:
211 If you run `configure' from a directory that contains source
212 directories for multiple libraries or programs, such as the `gdb-5.0'
213 source directory for version 5.0, `configure' creates configuration
214 files for every directory level underneath (unless you tell it not to,
215 with the `--norecursion' option).
217 You can run the `configure' script from any of the subordinate
218 directories in the GDB distribution, if you only want to configure that
219 subdirectory; but be sure to specify a path to it.
221 For example, with version 5.0, type the following to configure only
222 the `bfd' subdirectory:
227 You can install `gdb' anywhere; it has no hardwired paths. However,
228 you should make sure that the shell on your path (named by the `SHELL'
229 environment variable) is publicly readable. Remember that GDB uses the
230 shell to start your program--some systems refuse to let GDB debug child
231 processes whose programs are not readable.
234 Compiling GDB in another directory
235 ==================================
237 If you want to run GDB versions for several host or target machines,
238 you need a different `gdb' compiled for each combination of host and
239 target. `configure' is designed to make this easy by allowing you to
240 generate each configuration in a separate subdirectory, rather than in
241 the source directory. If your `make' program handles the `VPATH'
242 feature correctly (GNU `make' and SunOS 'make' are two that should),
243 running `make' in each of these directories builds the `gdb' program
246 To build `gdb' in a separate directory, run `configure' with the
247 `--srcdir' option to specify where to find the source. (You also need
248 to specify a path to find `configure' itself from your working
249 directory. If the path to `configure' would be the same as the
250 argument to `--srcdir', you can leave out the `--srcdir' option; it
253 For example, with version 5.0, you can build GDB in a separate
254 directory for a Sun 4 like this:
262 When `configure' builds a configuration using a remote source
263 directory, it creates a tree for the binaries with the same structure
264 (and using the same names) as the tree under the source directory. In
265 the example, you'd find the Sun 4 library `libiberty.a' in the
266 directory `gdb-sun4/libiberty', and GDB itself in `gdb-sun4/gdb'.
268 One popular reason to build several GDB configurations in separate
269 directories is to configure GDB for cross-compiling (where GDB runs on
270 one machine--the host--while debugging programs that run on another
271 machine--the target). You specify a cross-debugging target by giving
272 the `--target=TARGET' option to `configure'.
274 When you run `make' to build a program or library, you must run it
275 in a configured directory--whatever directory you were in when you
276 called `configure' (or one of its subdirectories).
278 The `Makefile' that `configure' generates in each source directory
279 also runs recursively. If you type `make' in a source directory such
280 as `gdb-5.0' (or in a separate configured directory configured with
281 `--srcdir=PATH/gdb-5.0'), you will build all the required libraries,
284 When you have multiple hosts or targets configured in separate
285 directories, you can run `make' on them in parallel (for example, if
286 they are NFS-mounted on each of the hosts); they will not interfere
290 Specifying names for hosts and targets
291 ======================================
293 The specifications used for hosts and targets in the `configure'
294 script are based on a three-part naming scheme, but some short
295 predefined aliases are also supported. The full naming scheme encodes
296 three pieces of information in the following pattern:
298 ARCHITECTURE-VENDOR-OS
300 For example, you can use the alias `sun4' as a HOST argument or in a
301 `--target=TARGET' option. The equivalent full name is
304 The `configure' script accompanying GDB does not provide any query
305 facility to list all supported host and target names or aliases.
306 `configure' calls the Bourne shell script `config.sub' to map
307 abbreviations to full names; you can read the script, if you wish, or
308 you can use it to test your guesses on abbreviations--for example:
314 % sh config.sub decstation
316 % sh config.sub hp300bsd
318 % sh config.sub i386v
320 % sh config.sub i786v
321 Invalid configuration `i786v': machine `i786v' not recognized
323 `config.sub' is also distributed in the GDB source directory
324 (`gdb-5.0', for version 5.0).
330 Here is a summary of the `configure' options and arguments that are
331 most often useful for building GDB. `configure' also has several other
332 options not listed here. *note : (configure.info)What Configure Does,
333 for a full explanation of `configure'.
338 [--norecursion] [--rm]
339 [--enable-build-warnings]
344 You may introduce options with a single `-' rather than `--' if you
345 prefer; but you may abbreviate option names if you use `--'.
348 Display a quick summary of how to invoke `configure'.
351 Configure the source to install programs and files under directory
355 *Warning: using this option requires GNU `make', or another `make'
356 that compatibly implements the `VPATH' feature.*
357 Use this option to make configurations in directories separate
358 from the GDB source directories. Among other things, you can use
359 this to build (or maintain) several configurations simultaneously,
360 in separate directories. `configure' writes configuration
361 specific files in the current directory, but arranges for them to
362 use the source in the directory PATH. `configure' will create
363 directories under the working directory in parallel to the source
364 directories below PATH.
367 Configure only the directory level where `configure' is executed;
368 do not propagate configuration to subdirectories.
371 Remove the configuration that the other arguments specify.
373 `--enable-build-warnings'
374 When building the GDB sources, ask the compiler to warn about any
375 code which looks even vaguely suspicious. You should only using
376 this feature if you're compiling with GNU CC. It passes the
387 Configure GDB for cross-debugging programs running on the specified
388 TARGET. Without this option, GDB is configured to debug programs
389 that run on the same machine (HOST) as GDB itself.
391 There is no convenient way to generate a list of all available
395 Configure GDB to run on the specified HOST.
397 There is no convenient way to generate a list of all available
401 Same as `--host=HOST'. If you omit this, GDB will guess; it's
404 `configure' accepts other options, for compatibility with configuring
405 other GNU tools recursively; but these are the only options that affect
406 GDB or its supporting libraries.
409 Languages other than C
410 =======================
412 See the GDB manual (gdb/doc/gdb.texinfo) for information on this.
418 Remote debugging over serial lines works fine, but the kernel
419 debugging code in here has not been tested in years. Van Jacobson has
420 better kernel debugging, but the UC lawyers won't let FSF have it.
426 The files m68k-stub.c, i386-stub.c, and sparc-stub.c are examples
427 of remote stubs to be used with remote.c. They are designed to run
428 standalone on an m68k, i386, or SPARC cpu and communicate properly
429 with the remote.c stub over a serial line.
431 The directory gdb/gdbserver/ contains `gdbserver', a program that
432 allows remote debugging for Unix applications. gdbserver is only
433 supported for some native configurations, including Sun 3, Sun 4, and
436 There are a number of remote interfaces for talking to existing ROM
437 monitors and other hardware:
439 remote-adapt.c AMD 29000 "Adapt"
440 remote-array.c Array Tech RAID controller
441 remote-bug.c Motorola BUG monitor
442 remote-e7000.c Hitachi E7000 ICE
443 remote-eb.c AMD 29000 "EBMON"
444 remote-es.c Ericsson 1800 monitor
445 remote-est.c EST emulator
446 remote-hms.c Hitachi Micro Systems H8/300 monitor
447 remote-mips.c MIPS remote debugging protocol
448 remote-mm.c AMD 29000 "minimon"
449 remote-nindy.c Intel 960 "Nindy"
450 remote-nrom.c NetROM ROM emulator
451 remote-os9k.c PC running OS/9000
452 remote-rdi.c ARM with Angel monitor
453 remote-rdp.c ARM with Demon monitor
454 remote-sds.c PowerPC SDS monitor
455 remote-sim.c Generalized simulator protocol
456 remote-st.c Tandem ST-2000 monitor
457 remote-udi.c AMD 29000 using the AMD "Universal Debug Interface"
458 remote-vx.c VxWorks realtime kernel
460 Remote-vx.c and the vx-share subdirectory contain a remote
461 interface for the VxWorks realtime kernel, which communicates over TCP
462 using the Sun RPC library. This would be a useful starting point for
463 other remote- via-ethernet back ends.
465 Remote-udi.c and the 29k-share subdirectory contain a remote
466 interface for AMD 29000 programs, which uses the AMD "Universal Debug
467 Interface". This allows GDB to talk to software simulators,
468 emulators, and/or bare hardware boards, via network or serial
469 interfaces. Note that GDB only provides an interface that speaks UDI,
470 not a complete solution. You will need something on the other end
471 that also speaks UDI.
477 The correct address for reporting bugs found in gdb is
478 "bug-gdb@gnu.org". Please email all bugs, and all requests for help
479 with GDB, to that address. Please include the GDB version number
480 (e.g., gdb-5.0), and how you configured it (e.g., "sun4" or "mach386
481 host, i586-intel-synopsys target"). Since GDB now supports so many
482 different configurations, it is important that you be precise about
483 this. If at all possible, you should include the actual banner that
484 GDB prints when it starts up, or failing that, the actual configure
485 command that you used when configuring GDB.
487 For more information on how/whether to report bugs, see the GDB
488 Bugs section of the GDB manual (gdb/doc/gdb.texinfo) or the
493 * Under Ultrix 4.2 (DECstation-3100) or Alphas under OSF/1, we have
494 seen problems with backtraces after interrupting the inferior out
495 of a read(). The problem is caused by ptrace() returning an
496 incorrect value for the frame pointer register (register 15 or
497 30). As far as we can tell, this is a kernel problem. Any help
498 with this would be greatly appreciated.
500 * Under Ultrix 4.4 (DECstation-3100), setting the TERMCAP environment
501 variable to a string without a trailing ':' can cause GDB to dump
502 core upon startup. Although the core file makes it look as though
503 GDB code failed, the crash actually occurs within a call to the
504 termcap library function tgetent(). The problem can be solved by
505 using the GNU Termcap library.
507 Alphas running OSF/1 (versions 1.0 through 2.1) have the same buggy
508 termcap code, but GDB behaves strangely rather than crashing.
510 * On DECstations there are warnings about shift counts out of range in
511 various BFD modules. None of them is a cause for alarm, they are actually
512 a result of bugs in the DECstation compiler.
514 * Notes for the DEC Alpha using OSF/1:
515 The debugging output of native cc has two known problems; we view these
517 The linker miscompacts symbol tables, which causes gdb to confuse the
518 type of variables or results in `struct <illegal>' type outputs.
519 dbx has the same problems with those executables. A workaround is to
520 specify -Wl,-b when linking, but that will increase the executable size
522 If a structure has incomplete type in one file (e.g., "struct foo *"
523 without a definition for "struct foo"), gdb will be unable to find the
524 structure definition from another file.
525 It has been reported that the Ultrix 4.3A compiler on decstations has the
528 * Notes for Solaris 2.x, using the SPARCworks cc compiler:
529 You have to compile your program with the -xs option of the SPARCworks
530 compiler to be able to debug your program with gdb.
531 Under Solaris 2.3 you also need patch 101409-03 (Jumbo linker patch).
532 Under Solaris 2.2, if you have patch 101052 installed, make sure
533 that it is at least at revision 101052-06.
535 * Under Irix 5 for SGIs, you must have installed the `compiler_dev.hdr'
536 subsystem that is on the IDO CD, otherwise you will get complaints
537 that certain files such as `/usr/include/syms.h' cannot be found.
539 * Under Irix 6 you must build with GCC. The vendor compiler reports
540 as errors certain assignments that GCC considers to be warnings.
542 GDB can produce warnings about symbols that it does not understand.
543 By default, these warnings are disabled. You can enable them by
544 executing `set complaint 10' (which you can put in your ~/.gdbinit if
545 you like). I recommend doing this if you are working on a compiler,
546 assembler, linker, or GDB, since it will point out problems that you
547 may be able to fix. Warnings produced during symbol reading indicate
548 some mismatch between the object file and GDB's symbol reading code.
549 In many cases, it's a mismatch between the specs for the object file
550 format, and what the compiler actually outputs or the debugger
551 actually understands.
554 Graphical interface to GDB -- X Windows, MS Windows
555 ==========================
557 Several graphical interfaces to GDB are available. You should
560 http://sourceware.cygnus.com/gdb/#gui
562 for an up-to-date list.
564 Emacs users will very likely enjoy the Grand Unified Debugger mode;
565 try typing `M-x gdb RET'. Those interested in experimenting with a
566 new kind of gdb-mode should load gdb/gdba.el into GNU Emacs 19.25 or
567 later. Comments on this mode are also welcome.
571 =====================
573 There is a lot of information about writing code for GDB in the
574 internals manual, distributed with GDB in gdb/doc/gdbint.texinfo. You
575 can read it by hand, print it by using TeX and texinfo, or process it
576 into an `info' file for use with Emacs' info mode or the standalone
579 If you are pondering writing anything but a short patch, especially
580 take note of the information about copyrights in the node Submitting
581 Patches. It can take quite a while to get all the paperwork done, so
582 we encourage you to start that process as soon as you decide you are
583 planning to work on something, or at least well ahead of when you
584 think you will be ready to submit the patches.
590 Included with the GDB distribution is a DejaGNU based testsuite
591 that can either be used to test your newly built GDB, or for
592 regression testing a GDB with local modifications.
594 Running the testsuite requires the prior installation of DejaGNU,
595 which is generally available via ftp. The directory
596 ftp://sourceware.cygnus.com/pub/dejagnu/ will contain a recent
597 snapshot. Once DejaGNU is installed, you can run the tests in one of
610 (3) cd gdb-5.0/gdb/testsuite
611 make site.exp (builds the site specific file)
612 runtest -tool gdb GDB=../gdb (or GDB=<somepath> as appropriate)
614 The last method gives you slightly more control in case of problems
615 with building one or more test executables or if you are using the
616 testsuite `standalone', without it being part of the GDB source tree.
618 See the DejaGNU documentation for further details.
621 (this is for editing this file with GNU emacs)