gcc/doc/configfiles.texi

@c Copyright (C) 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
@c This is part of the GCC manual.
@c For copying conditions, see the file gcc.texi.

@node Configuration Files
@chapter Files Created by @code{configure}

Here we spell out what files will be set up by @code{configure}.  Normally
you need not be concerned with these files.

@itemize @bullet
@item
A file named @file{config.h} is created that contains a @samp{#include}
of the top-level config file for the machine you will run the compiler
on (@pxref{Config}).  This file is responsible for defining information
about the host machine.  It includes @file{tm.h}.

The top-level config file is located in the subdirectory @file{config}.
Its name is always @file{xm-@var{something}.h}; usually
@file{xm-@var{machine}.h}, but there are some exceptions.

If your system does not support symbolic links, you might want to
set up @file{config.h} to contain a @samp{#include} command which
refers to the appropriate file.

@item
A file named @file{tconfig.h} is created which includes the top-level config
file for your target machine.  This is used for compiling certain
programs to run on that machine.

@item
A file named @file{tm.h} is created which includes the
machine-description macro file for your target machine.  It should be in
the subdirectory @file{config} and its name is often
@file{@var{machine}.h}.

@item
The command file @file{configure} also constructs the file
@file{Makefile} by adding some text to the template file
@file{Makefile.in}.  The additional text comes from files in the
@file{config} directory, named @file{t-@var{target}} and
@file{x-@var{host}}.  If these files do not exist, it means nothing
needs to be added for a given target or host.
@end itemize