-This is GDB, the GNU source-level debugger, presently running under
-un*x. This is a pre-alpha version of GDB version 4, and has NOT been
-extensively tested. It surely has some bugs, both bugs that were
-present in version 3 and new bugs. I have filed all the bug reports
-and fixes mailed to bug-gdb, and the fixes in particular will move
-into these sources as I find the time.
-
- => THIS VERSION IS FRAGILE! <=
-
- It depends on preliminary versions of a new "binary file
- descriptor" library, a new global "include" directory,
- and separate libraries for "readline" and "libiberty", which
- are packaged separately from GDB. You must obtain, configure
- and build these libraries manually, then configure and build gdb.
- When building gdb's for multiple platforms, you must manually
- rebuild the libraries separately for each platform. Yes, of
- course, we are working on this! FIXME!
-
- Configure and build the libraries for your host system by:
-
- cd ../bfd
- ./configure HOSTNAME
- make
-
- cd ../libiberty
- ./configure HOSTNAME
- make
-
- cd ../readline
- [edit Makefile as appropriate]
- make
-
- Then you can cd ../gdb-whatever, and config and build gdb.
-
-This release moves the generic GNU include files, the BFD library, the
-getopt routines, obstacks, and the readline library into the parent
-directory of gdb. The idea is that a variety of GNU tools can share a
-common copy of these things.
-
-A summary of features new since gdb-3.5 is in the file `WHATS.NEW'.
-
-The best way to build GDB, in my opinion, is in a subdirectory. I use
-a naming convention "=XXX" where XXX is the machine type I'm building
-for. Nothing depends on this, it's just how I remember which
-subdirectories are what. So, once you have the BFD library built for
-that machine, you can do:
-
- cd gdb-x.yy (the directory where this README is)
- mkdir =XXX (e.g. mkdir =vax)
- cd =XXX
- ../config.gdb machine
- make
+ README for gdb-4.9 release
+ Updated 10-May-93 by Fred Fish
+
+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-4.9 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.
-Machine is like "vax" or "sun4". For more information type `../config.gdb'.
+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:
+
+ Makefile.in config.sub* glob/ opcodes/
+ README configure* include/ readline/
+ bfd/ configure.in libiberty/ texinfo/
+ config/ etc/ mmalloc/
+ config.guess* gdb/ move-if-change*
+
+To build GDB, you can just do:
+
+ cd gdb-4.9
+ ./configure
+ make
+ cp gdb/gdb /usr/local/bin/gdb (or wherever you want)
-Once you have done that, just `make' will do everything, producing an
-executable `gdb' in this directory.
+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.
-You can also build gdb binaries in a completely different directory from its
-sources, by specifying "srcdir=YYY" to config.gdb, giving it an absolute
-or relative path to the source directory.
+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. You
-configure it this way by specifying `config.gdb host target' where host
-is where GDB runs, and target is where your program runs.
-
-If you want a new (current to this release) version of the manual, you
-will have to use the gdb.texinfo and texinfo.tex files provided with
-this distribution. For details see the texinfo manual (distributed
-with emacs and as a printed manual).
-
-About languages other than C...
-
-C++ support has been integrated into gdb. GDB should work with FORTRAN
-programs. (If you have problem, please send a bug report; note that you
-may have to refer to some FORTRAN variables with a trailing
-underscore). I am not aware of anyone who is working on getting it
-to use the syntax of any language other than C or C++. Pascal programs
-which use sets, subranges, file variables, or nested functions will not
+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-4.9/gdb/refcard.ps'.)
+If you can use PostScript or GhostScript with your printer, you can
+print the reference card immediately with `refcard.ps'.
+
+ The 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-4.9', 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++ progams. Partial Modula-2
+and Chill 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). Pascal programs which
+use sets, subranges, file variables, or nested functions will not
currently work.
-About kernel debugging...
+
+Kernel debugging
+=================
I have't done this myself so I can't really offer any advice.
-Remote debugging over serial lines is more like to be in a currently
-functioning state than the standalone gdb (kdb). FIXME.
-
-About remote debugging...
-
-[This section seems to be out of date, I have never seen the "rapp"
-program, though I would like to. FIXME.]
-`rapp' runs under unix and acts as a remote stub (like rem-multi.shar
-distributed with GDB version 3). Currently it just works over UDP
-(network), not over a serial line. To get it running
-* Compile GDB on the host machine as usual
-* Compile rapp on the target machine, giving for both host and target
- the type of the target machine
-* Install "gdb" in /etc/services on both machines.
-
-This will get reworked before the initial release of 4.x. FIXME.
-
-The files m68k-stub.c and i386-stub.c contain two examples of remote
-stubs to be used with remote.c. They are designeded to run standalone
-on a 68k or 386 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 be
-running on various different flavors of unix to allow debugging over a
+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.
-The files remote-eb.c and remote-nindy.c are two examples of remote
-interfaces for talking to existing ROM monitors (for the AMD 29000 and the
-Intel 960 repsectively). There is also a remote interface for the
-VxWorks realtime kernel, which communicates over TCP/IP, in remote-vx.c
-and the vx-share subdirectory.
+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), 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 register 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 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.
+
+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.
-About reporting bugs...
-The correct address for reporting bugs found with gdb is
-"bug-gdb@prep.ai.mit.edu". Please email all bugs to that address.
+Writing Code for GDB
+=====================
-About xgdb...
+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.
-xgdb is obsolete. We are not doing any development or support of it.
+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.
-There is an "xxgdb", which shows more promise.
-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.
+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.
-About the machine-dependent files...
-
-tconfig/<machine>
-This contains Makefile stuff for when the target system is <machine>.
-It also specifies the name of the tm-XXX.h file for this machine.
-
-xconfig/<machine>
-This contains Makefile stuff for when the host system is <machine>.
-It also specifies the name of the xm-XXX.h file for this machine.
-
-tm-XXX.h (tm.h is a link to this file, created by config.gdb).
-This file contains macro definitions that express information
-about the target machine's registers, stack frame format and instructions.
-
-xm-XXX.h (xm.h is a link to this file, created by config.gdb).
-This contains macro definitions describing the host system environment,
-such as byte order, host C compiler and library, ptrace support,
-and core file structure.
-
-<machine>-opcode.h
-<machine>-pinsn.c
-These files contain the information necessary to print instructions
-for your cpu type. <machine>-opcode.h includes some large initialized
-data structures, which is strange for a ".h" file, but it's OK since
-it is only included in one place. <machine>-opcode.h is shared
-between the debugger and the assembler (if the GNU assembler has been
-ported to that machine), whereas <machine>-pinsn.c is specific to GDB.
-
-<machine>-tdep.c
-This file contains any miscellaneous code required for this machine
-as a target. On some machines it doesn't exist at all. Its existence
-is specified in the tconfig/XXX file.
-
-<machine>-xdep.c
-This file contains any miscellaneous code required for this machine
-as a host. On some machines it doesn't exist at all. Its existence
-is specified in the xconfig/XXX file.
-
-infptrace.c
-This is the low level interface to inferior processes for systems
-using the Unix ptrace call in a vanilla way. Some systems have their
-own routines in <machine>-xdep.c. Whether or not it is used
-is specified in the xconfig/XXX file.
-
-coredep.c
-Machine and system-dependent aspects of reading core files. Some
-machines use coredep.c; some have the routines in <machine>-xdep.c.
-Whether or not it is used is specified in the xconfig/XXX file.
-Now that BFD is used to read core files, virtually all machines should
-use coredep.c and should just provide fetch_core_registers in
-<machine>-xdep.c.
-
-exec.c
-Machine and system-dependent aspects of reading executable files.
-Some machines use exec.c; some have the routines in <machine>-tdep.c
-Since BFD, virtually all machines should use exec.c.
-
-About writing code for GDB...
-
-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.
-
-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.
-
-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 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!
-
-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.
-
-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. Thus 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.
-
-About debugging gdb with itself...
-
-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 .
-
-Also, 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.
-
-When you run gdb in this 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.
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