-This is GDB, a source-level debugger intended for GNU,
-presently running under un*x.
+ README for gdb-4.9 release
+ Updated 10-May-93 by Fred Fish
-Before compiling GDB, you must set up links to five files according to
-the kind of machine you are running on. To do this, type `config.gdb
-machine', where machine is something like `vax' or `sun2'. This
-creates links named `param.h', `opcode.h', `pinsn.c', and `infdep.c'.
+This is GDB, the GNU source-level debugger, presently running under un*x.
+A summary of new features is in the file `NEWS'.
-Once these files are set up, just `make' will do everything,
-producing an executable `gdb' in this directory.
-About the machine-dependent files...
+Unpacking and Installation -- quick overview
+==========================
-m-<machine>.h
+In this release, the GDB debugger sources, the generic GNU include
+files, the BFD ("binary file description") library, the readline
+library, and other libraries all have directories of their own
+underneath the gdb-4.9 directory. The idea is that a variety of GNU
+tools can share a common copy of these things. Be aware of variation
+over time--for example don't try to build gdb with a copy of bfd from
+a release other than the gdb release (such as a binutils or gas
+release), especially if the releases are more than a few weeks apart.
+Configuration scripts and makefiles exist to cruise up and down this
+directory tree and automatically build all the pieces in the right
+order.
-This file contains macro definitions that express information
-about the machine's registers, stack frame format and instructions.
+When you unpack the gdb-4.9.tar.z or gdb-4.9.tar.Z file, you'll find
+a directory called `gdb-4.9', which contains:
-<machine>-opcode.h, <machine>-pinsn.c
-These files contain the information necessary to print instructions
-for your cpu type.
+ Makefile.in config.sub* glob/ opcodes/
+ README configure* include/ readline/
+ bfd/ configure.in libiberty/ texinfo/
+ config/ etc/ mmalloc/
+ config.guess* gdb/ move-if-change*
-<machine>-dep.c
-Those routines which provide a low level interface to ptrace and which
-tend to be machine-dependent. (The machine-independent routines are in
-`infrun.c' and `inflow.c')
+To build GDB, you can just do:
-About debugging gdb with itself...
+ cd gdb-4.9
+ ./configure
+ make
+ cp gdb/gdb /usr/local/bin/gdb (or wherever you want)
-You probably want to do a "make TAGS" after you configure your
-distribution; this will put the machine dependent routines for your
-local machine where they will be accessed first by a M-period .
+This will configure and build all the libraries as well as GDB.
+If `configure' can't determine your system type, specify one as its
+argument, e.g. sun4 or decstation.
-Also, you want to make sure that gdb is not compiled with shared
-libraries on the Sun 4. And you want to make sure that you've
-compiled gdb with your local cc or taken appropriate precautions
-regarding ansification of include files. See the Makefile for more
-information.
+If you get compiler warnings during this stage, see the `Reporting Bugs'
+section below; there are a few known problems.
-The "info" command, when executed without a subcommand in a gdb being
-debugged by gdb, will pop you back up to the top level gdb. See
-.gdbinit for more details.
+GDB can be used as a cross-debugger, running on a machine of one type
+while debugging a program running on a machine of another type. See below.
-About languages other than C...
-C++ support has been integrated into gdb; it works, but somewhat
-buggily. Pascal support has not yet been integrated in gdb; the work
-is being done.
+More Documentation
+******************
-About reporting bugs...
+ The GDB 4 release includes an already-formatted reference card,
+ready for printing with PostScript or GhostScript, in the `gdb'
+subdirectory of the main source directory. (In `gdb-4.9/gdb/refcard.ps'.)
+If you can use PostScript or GhostScript with your printer, you can
+print the reference card immediately with `refcard.ps'.
-The correct address for reporting bugs found with gdb is
-"bug-gdb@prep.ai.mit.edu". Please send all bugs to that address.
+ The release also includes the source for the reference card. You
+can format it, using TeX, by typing:
-About xgdb...
+ make refcard.dvi
-xgdb.c was provided to us by the user community; it is not an integral
-part of the gdb distribution. The problem of providing visual
-debugging support on top of gdb is peripheral to the GNU project and
-(at least right now) we can't afford to put time into it. So while we
-will be happy to incorporate user fixes to xgdb.c, we do not guarantee
-that it will work and we will not fix bugs reported in it.
+ The GDB reference card is designed to print in landscape mode on US
+"letter" size paper; that is, on a sheet 11 inches wide by 8.5 inches
+high. You will need to specify this form of printing as an option to
+your DVI output program.
-For those intersted in auto display of source and the availability of
-an editor while debugging I suggest trying gdb-mode in gnu-emacs.
-Comments on this mode are welcome.
+ All the documentation for GDB comes as part of the machine-readable
+distribution. The documentation is written in Texinfo format, which is
+a documentation system that uses a single source file to produce both
+on-line information and a printed manual. You can use one of the Info
+formatting commands to create the on-line version of the documentation
+and TeX (or `texi2roff') to typeset the printed version.
+ GDB includes an already formatted copy of the on-line Info version of
+this manual in the `gdb' subdirectory. The main Info file is
+`gdb-VERSION-NUMBER/gdb/gdb.info', and it refers to subordinate files
+matching `gdb.info*' in the same directory. If necessary, you can
+print out these files, or read them with any editor; but they are
+easier to read using the `info' subsystem in GNU Emacs or the
+standalone `info' program, available as part of the GNU Texinfo
+distribution.
+
+ If you want to format these Info files yourself, you need one of the
+Info formatting programs, such as `texinfo-format-buffer' or `makeinfo'.
+
+ If you have `makeinfo' installed, and are in the top level GDB
+source directory (`gdb-4.9', in the case of version 4.9), you can make
+the Info file by typing:
+
+ cd gdb
+ make gdb.info
+
+ If you want to typeset and print copies of this manual, you need TeX,
+a program to print its DVI output files, and `texinfo.tex', the Texinfo
+definitions file.
+
+ TeX is a typesetting program; it does not print files directly, but
+produces output files called DVI files. To print a typeset document,
+you need a program to print DVI files. If your system has TeX
+installed, chances are it has such a program. The precise command to
+use depends on your system; `lpr -d' is common; another (for PostScript
+devices) is `dvips'. The DVI print command may require a file name
+without any extension or a `.dvi' extension.
+
+ TeX also requires a macro definitions file called `texinfo.tex'.
+This file tells TeX how to typeset a document written in Texinfo
+format. On its own, TeX cannot read, much less typeset a Texinfo file.
+ `texinfo.tex' is distributed with GDB and is located in the
+`gdb-VERSION-NUMBER/texinfo' directory.
+
+ If you have TeX and a DVI printer program installed, you can typeset
+and print this manual. First switch to the the `gdb' subdirectory of
+the main source directory (for example, to `gdb-4.9/gdb') and then type:
+
+ make gdb.dvi
+
+
+Installing GDB
+**************
+
+ GDB comes with a `configure' script that automates the process of
+preparing GDB for installation; you can then use `make' to build the
+`gdb' program.
+
+ The GDB distribution includes all the source code you need for GDB in
+a single directory, whose name is usually composed by appending the
+version number to `gdb'.
+
+ For example, the GDB version 4.9 distribution is in the `gdb-4.9'
+directory. That directory contains:
+
+`gdb-4.9/configure (and supporting files)'
+ script for configuring GDB and all its supporting libraries.
+
+`gdb-4.9/gdb'
+ the source specific to GDB itself
+
+`gdb-4.9/bfd'
+ source for the Binary File Descriptor library
+
+`gdb-4.9/include'
+ GNU include files
+
+`gdb-4.9/libiberty'
+ source for the `-liberty' free software library
+
+`gdb-4.9/opcodes'
+ source for the library of opcode tables and disassemblers
+
+`gdb-4.9/readline'
+ source for the GNU command-line interface
+
+`gdb-4.9/glob'
+ source for the GNU filename pattern-matching subroutine
+
+`gdb-4.9/mmalloc'
+ source for the GNU memory-mapped malloc package
+
+'gdb-4.9/sim'
+ source for some simulators (z8000, H8/300, H8/500, etc)
+
+ The simplest way to configure and build GDB is to run `configure'
+from the `gdb-VERSION-NUMBER' source directory, which in this example
+is the `gdb-4.9' directory.
+
+ First switch to the `gdb-VERSION-NUMBER' source directory if you are
+not already in it; then run `configure'. Pass the identifier for the
+platform on which GDB will run as an argument.
+
+ For example:
+
+ cd gdb-4.9
+ ./configure HOST
+ make
+
+where HOST is an identifier such as `sun4' or `decstation', that
+identifies the platform where GDB will run.
+
+ Running `configure HOST' followed by `make' builds the `bfd',
+`readline', `mmalloc', and `libiberty' libraries, then `gdb' itself.
+The configured source files, and the binaries, are left in the
+corresponding source directories.
+
+ `configure' is a Bourne-shell (`/bin/sh') script; if your system
+does not recognize this automatically when you run a different shell,
+you may need to run `sh' on it explicitly:
+
+ sh configure HOST
+
+ If you run `configure' from a directory that contains source
+directories for multiple libraries or programs, such as the `gdb-4.9'
+source directory for version 4.9, `configure' creates configuration
+files for every directory level underneath (unless you tell it not to,
+with the `--norecursion' option).
+
+ You can run the `configure' script from any of the subordinate
+directories in the GDB distribution, if you only want to configure that
+subdirectory; but be sure to specify a path to it.
+
+ For example, with version 4.9, type the following to configure only
+the `bfd' subdirectory:
+
+ cd gdb-4.9/bfd
+ ../configure HOST
+
+ You can install `gdb' anywhere; it has no hardwired paths. However,
+you should make sure that the shell on your path (named by the `SHELL'
+environment variable) is publicly readable. Remember that GDB uses the
+shell to start your program--some systems refuse to let GDB debug child
+processes whose programs are not readable.
+
+
+Compiling GDB in another directory
+==================================
+
+ If you want to run GDB versions for several host or target machines,
+you need a different `gdb' compiled for each combination of host and
+target. `configure' is designed to make this easy by allowing you to
+generate each configuration in a separate subdirectory, rather than in
+the source directory. If your `make' program handles the `VPATH'
+feature correctly (GNU `make' and SunOS 'make' are two that should),
+running `make' in each of these directories builds the `gdb' program
+specified there.
+
+ To build `gdb' in a separate directory, run `configure' with the
+`--srcdir' option to specify where to find the source. (You also need
+to specify a path to find `configure' itself from your working
+directory. If the path to `configure' would be the same as the
+argument to `--srcdir', you can leave out the `--srcdir' option; it
+will be assumed.)
+
+ For example, with version 4.9, you can build GDB in a separate
+directory for a Sun 4 like this:
+
+ cd gdb-4.9
+ mkdir ../gdb-sun4
+ cd ../gdb-sun4
+ ../gdb-4.9/configure sun4
+ make
+
+ When `configure' builds a configuration using a remote source
+directory, it creates a tree for the binaries with the same structure
+(and using the same names) as the tree under the source directory. In
+the example, you'd find the Sun 4 library `libiberty.a' in the
+directory `gdb-sun4/libiberty', and GDB itself in `gdb-sun4/gdb'.
+
+ One popular reason to build several GDB configurations in separate
+directories is to configure GDB for cross-compiling (where GDB runs on
+one machine--the host--while debugging programs that run on another
+machine--the target). You specify a cross-debugging target by giving
+the `--target=TARGET' option to `configure'.
+
+ When you run `make' to build a program or library, you must run it
+in a configured directory--whatever directory you were in when you
+called `configure' (or one of its subdirectories).
+
+ The `Makefile' that `configure' generates in each source directory
+also runs recursively. If you type `make' in a source directory such
+as `gdb-4.9' (or in a separate configured directory configured with
+`--srcdir=PATH/gdb-4.9'), you will build all the required libraries,
+and then build GDB.
+
+ When you have multiple hosts or targets configured in separate
+directories, you can run `make' on them in parallel (for example, if
+they are NFS-mounted on each of the hosts); they will not interfere
+with each other.
+
+
+Specifying names for hosts and targets
+======================================
+
+ The specifications used for hosts and targets in the `configure'
+script are based on a three-part naming scheme, but some short
+predefined aliases are also supported. The full naming scheme encodes
+three pieces of information in the following pattern:
+
+ ARCHITECTURE-VENDOR-OS
+
+ For example, you can use the alias `sun4' as a HOST argument or in a
+`--target=TARGET' option. The equivalent full name is
+`sparc-sun-sunos4'.
+
+ The `configure' script accompanying GDB does not provide any query
+facility to list all supported host and target names or aliases.
+`configure' calls the Bourne shell script `config.sub' to map
+abbreviations to full names; you can read the script, if you wish, or
+you can use it to test your guesses on abbreviations--for example:
+
+ % sh config.sub sun4
+ sparc-sun-sunos411
+ % sh config.sub sun3
+ m68k-sun-sunos411
+ % sh config.sub decstation
+ mips-dec-ultrix42
+ % sh config.sub hp300bsd
+ m68k-hp-bsd
+ % sh config.sub i386v
+ i386-unknown-sysv
+ % sh config.sub i786v
+ Invalid configuration `i786v': machine `i786v' not recognized
+
+`config.sub' is also distributed in the GDB source directory
+(`gdb-4.9', for version 4.9).
+
+
+`configure' options
+===================
+
+ Here is a summary of the `configure' options and arguments that are
+most often useful for building GDB. `configure' also has several other
+options not listed here. *note : (configure.info)What Configure Does,
+for a full explanation of `configure'.
+
+ configure [--help]
+ [--prefix=DIR]
+ [--srcdir=PATH]
+ [--norecursion] [--rm]
+ [--target=TARGET] HOST
+
+You may introduce options with a single `-' rather than `--' if you
+prefer; but you may abbreviate option names if you use `--'.
+
+`--help'
+ Display a quick summary of how to invoke `configure'.
+
+`-prefix=DIR'
+ Configure the source to install programs and files under directory
+ `DIR'.
+
+`--srcdir=PATH'
+ *Warning: using this option requires GNU `make', or another `make'
+ that compatibly implements the `VPATH' feature.*
+ Use this option to make configurations in directories separate
+ from the GDB source directories. Among other things, you can use
+ this to build (or maintain) several configurations simultaneously,
+ in separate directories. `configure' writes configuration
+ specific files in the current directory, but arranges for them to
+ use the source in the directory PATH. `configure' will create
+ directories under the working directory in parallel to the source
+ directories below PATH.
+
+`--norecursion'
+ Configure only the directory level where `configure' is executed;
+ do not propagate configuration to subdirectories.
+
+`--rm'
+ Remove the configuration that the other arguments specify.
+
+`--target=TARGET'
+ Configure GDB for cross-debugging programs running on the specified
+ TARGET. Without this option, GDB is configured to debug programs
+ that run on the same machine (HOST) as GDB itself.
+
+ There is no convenient way to generate a list of all available
+ targets.
+
+`HOST ...'
+ Configure GDB to run on the specified HOST.
+
+ There is no convenient way to generate a list of all available
+ hosts.
+
+`configure' accepts other options, for compatibility with configuring
+other GNU tools recursively; but these are the only options that affect
+GDB or its supporting libraries.
+
+
+Languages other than C
+=======================
+
+GDB provides some support for debugging C++ programs, however that support
+only works well with GNU C++, and even then only on systems that use stabs
+debugging format. In particular, cfront based compilers such as Sun's C++
+are not fully supported.
+
+GDB should work with FORTRAN programs. If you have problems, please send a
+bug report; you may have to refer to some FORTRAN variables with a trailing
+underscore.
+
+Pascal programs which use sets, subranges, file variables, or nested functions
+will not currently work.
+
+Partial Modula-2 and Chill support is now in GDB.
+
+
+Kernel debugging
+=================
+
+I have't done this myself so I can't really offer any advice.
+Remote debugging over serial lines works fine, but the kernel debugging
+code in here has not been tested in years. Van Jacobson has
+better kernel debugging, but the UC lawyers won't let FSF have it.
+
+
+Remote debugging
+=================
+
+The files m68k-stub.c, i386-stub.c, and sparc-stub.c are examples of
+remote stubs to be used with remote.c. They are designed to run
+standalone on an m68k, i386, or SPARC cpu and communicate properly with
+the remote.c stub over a serial line.
+
+The file rem-multi.shar contains a general stub that can probably
+run on various different flavors of unix to allow debugging over a
+serial line from one machine to another.
+
+Some working remote interfaces for talking to existing ROM monitors
+are:
+ remote-adapt.c AMD 29000 "Adapt"
+ remote-eb.c AMD 29000 "EBMON"
+ remote-es1800.c Ericsson 1800 monitor
+ remote-hms.c Hitachi Micro Systems H8/300 monitor
+ remote-mips.c MIPS remote debugging protocol
+ remote-mm.c AMD 29000 "minimon"
+ remote-nindy.c Intel 960 "Nindy"
+ remote-sim.c Generalized simulator protocol
+ remote-st2000.c Tandem ST-2000 monitor
+ remote-udi.c AMD 29000 using the AMD "Universal Debug Interface"
+ remote-vx.c VxWorks realtime kernel
+ remote-z8k.c Zilog Z8000 simulator
+
+Remote-vx.c and the vx-share subdirectory contain a remote interface for the
+VxWorks realtime kernel, which communicates over TCP using the Sun
+RPC library. This would be a useful starting point for other remote-
+via-ethernet back ends.
+
+Remote-udi.c and the 29k-share subdirectory contain a remote interface
+for AMD 29000 programs, which uses the AMD "Universal Debug Interface".
+This allows GDB to talk to software simulators, emulators, and/or bare
+hardware boards, via network or serial interfaces. Note that GDB only
+provides an interface that speaks UDI, not a complete solution. You
+will need something on the other end that also speaks UDI.
+
+
+Reporting Bugs
+===============
+
+The correct address for reporting bugs found in gdb is
+"bug-gdb@prep.ai.mit.edu". Please email all bugs, and all requests for
+help with GDB, to that address. Please include the GDB version number
+(e.g. gdb-4.9), and how you configured it (e.g. "sun4" or "mach386
+host, i586-intel-synopsys target"). If you include the banner that GDB
+prints when it starts up, that will give us enough information.
+
+For more information on how/whether to report bugs, see the GDB Bugs
+section of the GDB manual (gdb/doc/gdb.texinfo).
+
+Known bugs:
+
+ * Under Ultrix 4.2 (DECstation-3100) or Alphas under OSF/1, we have
+ seen problems with backtraces after interrupting the inferior out
+ of a read(). The problem is caused by ptrace() returning an
+ incorrect value for the frame pointer register (register 15 or
+ 30). As far as we can tell, this is a kernel problem. Any help
+ with this would be greatly appreciated.
+
+ * On the SPARC GDB reports incorrect values of struct arguments to
+ functions, for the seventh and subsequent arguments. We have been looking
+ at this but no fix is available yet.
+
+ * On DECstations there are warnings about shift counts out of range in
+ various BFD modules. None of them is a cause for alarm, they are actually
+ a result of bugs in the DECstation compiler.
+
+ * On Solaris (2.1, at least) using the "run" command when the program
+ is already running restarts the program, but may leave a core dump
+ from the previous execution in the current directory. Other SVR4
+ based systems don't seem to have this problem, using the same gdb
+ source code.
+
+ * Notes for the DEC Alpha using OSF/1:
+ The debugging output of native cc has two known problems; we view these
+ as compiler bugs.
+ The linker miscompacts symbol tables, which causes gdb to confuse the
+ type of variables or results in `struct <illegal>' type outputs.
+ dbx has the same problems with those executables. A workaround is to
+ specify -Wl,-b when linking, but that will increase the executable size
+ considerably.
+ If a structure has incomplete type in one file (e.g. "struct foo *"
+ without a definition for "struct foo"), gdb will be unable to find the
+ structure definition from another file.
+ It has been reported that the Ultrix 4.3A compiler on decstations has the
+ same problems.
+
+ If you intend to compile gdb with gcc-2.4.5, be warned that the file
+ bfd/libbfd.c will be miscompiled due to a bug in gcc, you have
+ to compile this file with native cc. You will get many warnings from
+ gcc while compiling gdb, but these can be ignored for now. Again, these
+ problems are Alpha-specific.
+
+GDB can produce warnings about symbols that it does not understand. By
+default, these warnings are disabled. You can enable them by executing
+`set complaint 10' (which you can put in your ~/.gdbinit if you like).
+I recommend doing this if you are working on a compiler, assembler,
+linker, or gdb, since it will point out problems that you may be able
+to fix. Warnings produced during symbol reading indicate some mismatch
+between the object file and GDB's symbol reading code. In many cases,
+it's a mismatch between the specs for the object file format, and what
+the compiler actually outputs or the debugger actually understands.
+
+
+X Windows versus GDB
+=====================
+
+There is an "xxgdb", which seems to work for simple operations,
+which was posted to comp.sources.x.
+
+For those interested in auto display of source and the availability of
+an editor while debugging I suggest trying gdb-mode in gnu-emacs
+(Try typing M-x gdb RETURN). Comments on this mode are welcome.
+
+
+Writing Code for GDB
+=====================
+
+There is a lot of information about writing code for GDB in the
+internals manual, distributed with GDB in gdb/doc/gdbint.texinfo. You
+can read it by hand, print it by using TeX and texinfo, or process it
+into an `info' file for use with Emacs' info mode or the standalone
+`info' program. In particular, see the nodes Getting Started,
+Debugging GDB, New Architectures, Coding Style, Clean Design, and
+Submitting Patches.
+
+If you are pondering writing anything but a short patch, especially
+take note of the information about copyrights in the node Submitting
+Patches. It can take quite a while to get all the paperwork done, so
+we encourage you to start that process as soon as you decide you are
+planning to work on something, or at least well ahead of when you
+think you will be ready to submit the patches.
+
+
+GDB Testsuite
+=============
+
+There is a dejagnu based testsuite available for testing your newly
+built gdb, or for regression testing gdb's with local modifications.
+The testsuite is distributed separately from the base gdb distribution
+for the convenience of people that wish to get either gdb or the testsuite
+separately.
+
+The name of the testsuite is gdb-4.9-testsuite.tar.z. You unpack it in the
+same directory in which you unpacked the base gdb distribution, and it
+will create and populate the directory gdb-4.9/gdb/testsuite.
+
+Running the testsuite requires the prior installation of dejagnu, which
+should be available via ftp. Once dejagnu is installed, you can run
+the tests in one of two ways:
+
+ (1) cd gdb-4.9/gdb (assuming you also unpacked gdb)
+ make check
+
+or
+
+ (2) cd gdb-4.9/gdb/testsuite
+ make (builds the test executables)
+ make site.exp (builds the site specific file)
+ runtest -tool gdb GDB=../gdb (or GDB=<somepath> as appropriate)
+
+The second method gives you slightly more control in case of problems with
+building one or more test executables, in case you wish to remove some
+test executables before running the tests, or if you are using the testsuite
+'standalone', without it being part of the gdb source tree.
+
+See the dejagnu documentation for further details.
+
+\f
+(this is for editing this file with GNU emacs)
+Local Variables:
+mode: text
+End: