-This is GDB, a source-level debugger intended for GNU,
-presently running under un*x.
-
-Before compiling GDB, you must set three files according to
-the kind of machine you are running on.
-
-param.h must be set up to #include an m- file for the machine.
-The m- files written so far are m-vax.h, m-sun2.h and m-sun3.h.
-(I believe that it is the operating system version and not
-the cpu type which determines which of the two is right on a Sun.)
-This file contains macro definitions that express information
-about the machine's registers, stack frame format and instructions.
-
-initialize.h must be set up to #include an m-...init.h file.
-There are two of them written: m-vaxinit.h and m-suninit.h.
-This file defines one macro, which says how to round up from the
-address of the end of the text of one .o file to the beginning of
-the text of the next .o file.
-
-pinsn.c must be set up to include the instruction printer for
-your cpu type. The two printers that exist are vax-pinsn.c
-and m68k-pinsn.c.
-
-`Makefile' must be changed to say `OBSTACK = obstack.o' instead of
-`OBSTACK=-lobstack' (unless you want to install obstack.o as
-/lib/libobstack.a).
-
-Once these files are set up, just `make' will do everything,
-producing an executable `gdb' in this directory.
+ README for gdb-4.7 release
+ Stu Grossman & John Gilmore 23 October 1992
+
+This is GDB, the GNU source-level debugger, presently running under un*x.
+A summary of new features is in the file `NEWS'.
+
+
+Unpacking and Installation -- quick overview
+==========================
+
+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-4.7 directory. The idea is that a variety of GNU tools can
+share a common copy of these things. Configuration scripts and
+makefiles exist to cruise up and down this directory tree and
+automatically build all the pieces in the right order.
+
+When you unpack the gdb-4.7.tar.Z file, you'll get a directory called
+`gdb-4.7', which contains:
+
+ COPYING.LIB config/ configure.texi mmalloc/
+ Makefile.in config.sub* gdb/ move-if-change*
+ README configure* glob/ opcodes/
+ bfd/ configure.in include/ readline/
+ cfg-paper.texi configure.man libiberty/ texinfo/
+
+To build GDB, you can just do:
+
+ cd gdb-4.7
+ ./configure HOSTTYPE (e.g. sun4, decstation)
+ make
+ cp gdb/gdb /usr/local/bin/gdb (or wherever you want)
+
+This will configure and build all the libraries as well as GDB.
+If you get compiler warnings during this stage, see the `Reporting Bugs'
+section below; there are a few known problems.
+
+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.
+
+
+More Documentation
+******************
+
+ 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-4.7/gdb/refcard.ps' of the
+version 4.7 release. If you can use PostScript or GhostScript with your
+printer, you can print the reference card immediately with `refcard.ps'.
+
+ The release also includes the source for the reference card. You
+can format it, using TeX, by typing:
+
+ make refcard.dvi
+
+ 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.
+
+ 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-4.7', in the case of version 4.7), 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 printing program such as `lpr', and `texinfo.tex', the Texinfo
+definitions file.
+
+ TeX is 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 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-4.7/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
+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 4.7 distribution is in the `gdb-4.7'
+directory. That directory contains:
+
+`gdb-4.7/configure (and supporting files)'
+ script for configuring GDB and all its supporting libraries.
+
+`gdb-4.7/gdb'
+ the source specific to GDB itself
+
+`gdb-4.7/bfd'
+ source for the Binary File Descriptor library
+
+`gdb-4.7/include'
+ GNU include files
+
+`gdb-4.7/libiberty'
+ source for the `-liberty' free software library
+
+`gdb-4.7/opcodes'
+ source for the library of opcode tables and disassemblers
+
+`gdb-4.7/readline'
+ source for the GNU command-line interface
+
+`gdb-4.7/glob'
+ source for the GNU filename pattern-matching subroutine
+
+`gdb-4.7/mmalloc'
+ source for the GNU memory-mapped malloc package
+
+ 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-4.7' 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-4.7
+ ./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-4.7'
+source directory for version 4.7, `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 4.7, type the following to configure only
+the `bfd' subdirectory:
+
+ cd gdb-4.7/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'll 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 (GNU `make' does), running `make' in each of these directories
+then 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'll 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 4.7, you can build GDB in a separate
+directory for a Sun 4 like this:
+
+ cd gdb-4.7
+ mkdir ../gdb-sun4
+ cd ../gdb-sun4
+ ../gdb-4.7/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' generated by `configure' for each source directory
+also runs recursively. If you type `make' in a source directory such
+as `gdb-4.7' (or in a separate configured directory configured with
+`--srcdir=PATH/gdb-4.7'), you will build all the required libraries,
+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, but 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-4.7', for version 4.7).
+
+
+`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 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++ progams. Partial Modula-2
+support is now in GDB. 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). I am not aware of
+anyone who is working on getting gdb to use the syntax of any other
+language. Pascal programs which use sets, subranges, file variables,
+or nested functions will not currently work.
+
+
+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 a 68k, 386, 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-eb.c AMD 29000 "EBMON"
+ remote-hms.c Hitachi Micro Systems H8/300 monitor
+ remote-nindy.c Intel 960 "Nindy"
+ remote-adapt.c AMD 29000 "Adapt"
+ remote-mm.c AMD 29000 "minimon"
+
+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.
+
+
+Reporting Bugs
+===============
+
+The correct address for reporting bugs found in gdb is
+"bug-gdb@prep.ai.mit.edu". Please email all bugs to that address.
+Please include the GDB version number (e.g. gdb-4.7), and how
+you configured it (e.g. "sun4" or "mach386 host, i586-intel-synopsys
+target").
+
+A known bug:
+
+ * If you run with a watchpoint enabled, breakpoints will become
+ erratic and might not stop the program. Disabling or deleting the
+ watchpoint will fix the problem.
+
+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.
+
+If you port gdb to a new machine, please send the required changes to
+bug-gdb@prep.ai.mit.edu. There's lots of information about doing your
+own port in the file gdb-4.7/gdb/doc/gdbint.texinfo, which you can
+print out, or read with `info' (see the Makefile.in there). If your
+changes are more than a few lines, obtain and send in a copyright
+assignment from gnu@prep.ai.mit.edu, as described in the section
+`Writing Code for GDB' below.
+
+
+X Windows versus GDB
+=====================
+
+xgdb is obsolete. We are not doing any development or support of it.
+
+There is an "xxgdb", which shows more promise, which was posted to
+comp.sources.x.
+
+For those intersted 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
+=====================
+
+Documentation about GDB's internals is in the subdirectory doc, as
+`gdbint.texinfo'. In particular, there is a `cookbook' there on how
+to port GDB to a new machine. 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.
+
+We appreciate having users contribute code that is of general use, but
+for it to be included in future GDB releases it must be cleanly
+written. We do not want to include changes that will needlessly make
+future maintainance difficult. It is not much harder to do things
+right, and in the long term it is worth it to the GNU project, and
+probably to you individually as well.
+
+If you make substantial changes, you'll have to file a copyright
+assignment with the Free Software Foundation before we can produce a
+release that includes your changes. Send mail requesting the copyright
+assignment to gnu@prep.ai.mit.edu. Do this early, like before the
+changes actually work, or even before you start them, because a manager
+or lawyer on your end will probably make this a slow process.
+
+Please code according to the GNU coding standards. If you do not have
+a copy, you can request one by sending mail to gnu@prep.ai.mit.edu.
+
+Please try to avoid making machine-specific changes to
+machine-independent files. If this is unavoidable, put a hook in the
+machine-independent file which calls a (possibly) machine-dependent
+macro (for example, the IGNORE_SYMBOL macro can be used for any
+symbols which need to be ignored on a specific machine. Calling
+IGNORE_SYMBOL in dbxread.c is a lot cleaner than a maze of #if
+defined's). The machine-independent code should do whatever "most"
+machines want if the macro is not defined in param.h. Using #if
+defined can sometimes be OK (e.g. SET_STACK_LIMIT_HUGE) but should be
+conditionalized on a specific feature of an operating system (set in
+tm.h or xm.h) rather than something like #if defined(vax) or #if
+defined(SYSV). If you use an #ifdef on some symbol that is defined
+in a header file (e.g. #ifdef TIOCSETP), *please* make sure that you
+have #include'd the relevant header file in that module!
+
+There is a list of all known `feature-test macros' in gdbint.texinfo.
+Each such macro should be defined (or left undefined) in a host-dependent,
+target-dependent, or native-dependent include file. Not all of the
+macros are cleanly separated this way, yet. As you make changes, move
+the code toward cleanliness.
+
+It is better to replace entire routines which may be system-specific,
+rather than put in a whole bunch of hooks which are probably not going
+to be helpful for any purpose other than your changes. For example,
+if you want to modify dbxread.c to deal with DBX debugging symbols
+which are in COFF files rather than BSD a.out files, do something
+along the lines of a macro GET_NEXT_SYMBOL, which could have
+different definitions for COFF and a.out, rather than trying to put
+the necessary changes throughout all the code in dbxread.c that
+currently assumes BSD format.
+
+When generalizing GDB along a particular interface, please use an
+attribute-struct rather than inserting tests or switch statements
+everywhere. For example, GDB has been generalized to handle multiple
+kinds of remote interfaces -- not by #ifdef's everywhere, but by
+defining the "target_ops" structure and having a current target (as
+well as a stack of targets below it, for memory references). Whenever
+something needs to be done that depends on which remote interface we
+are using, a flag in the current target_ops structure is tested (e.g.
+`target_has_stack'), or a function is called through a pointer in the
+current target_ops structure. In this way, when a new remote interface
+is added, only one module needs to be touched -- the one that actually
+implements the new remote interface. Other examples of
+attribute-structs are BFD access to multiple kinds of object file
+formats, or GDB's access to multiple source languages.
+
+Please avoid duplicating code. For example, in GDB 3.x all the stuff
+in infptrace.c was duplicated in *-dep.c, and so changing something
+was very painful. In GDB 4.x, these have all been consolidated
+into infptrace.c. infptrace.c can deal with variations between
+systems the same way any system-independent file would (hooks, #if
+defined, etc.), and machines which are radically different don't need
+to use infptrace.c at all. The same was true of core_file_command
+and exec_file_command.
+
+
+Debugging gdb with itself
+==========================
+
+If gdb is limping on your machine, this is the preferred way to get it
+fully functional. Be warned that in some ancient Unix systems, like
+Ultrix 4.0, a program can't be running in one process while it is being
+debugged in another. Rather than doing "./gdb ./gdb", which works on
+Suns and such, you can copy gdb to gdb2 and then do "./gdb ./gdb2".
+
+When you run gdb in the gdb source directory, it will read a ".gdbinit"
+file that sets up some simple things to make debugging gdb easier. 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 details.
+
+I strongly recommend printing out the reference card and using it.
+Send reference-card suggestions to bug-gdb@prep.ai.mit.edu, just like bugs.
+
+If you use emacs, you will 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.
+
+Also, make sure that you've either compiled gdb with your local cc, or
+have run `fixincludes' if you are compiling with gcc.
+\f
+(this is for editing this file with GNU emacs)
+Local Variables:
+mode: text
+End: