@setfilename configure.info
@settitle Cygnus Configure
@c %**end of header
+@synindex ky cp
+@tex
+\def\$#1${{#1}} % Kluge: collect RCS revision info without $...$
+\xdef\manvers{\$Revision$} % For use in headers, footers too
+@end tex
@setchapternewpage off
+@ifinfo
+@format
+START-INFO-DIR-ENTRY
+* configure: (configure). Cygnus configure.
+END-INFO-DIR-ENTRY
+@end format
+@end ifinfo
+
@ifinfo
This document attempts to describe the Cygnus Support version of
@code{configure}.
-Copyright (C) 1991 Cygnus Support
+Copyright (C) 1991, 1992 Cygnus Support
Permission is granted to make and distribute verbatim copies of
this manual provided the copyright notice and this permission notice
are preserved on all copies.
@titlepage
@sp 10
@title{Cygnus Configure}
-@subtitle Edition ``$Revision$'' for Cygnus Configure version 1.84
+@subtitle @manvers, for Cygnus Configure version 1.84
@author{K. Richard Pixley, @code{rich@@cygnus.com}}
@author{Cygnus Support}
@page
@vskip 0pt plus 1filll
-Copyright @copyright{} 1991 Cygnus Support
+Copyright @copyright{} 1991, 1992 Cygnus Support
Permission is granted to make and distribute verbatim copies of
this manual provided the copyright notice and this permission notice
@end titlepage
@ifinfo
-@format
-START-INFO-DIR-ENTRY
-* configure: (configure.info). Cygnus configure.
-END-INFO-DIR-ENTRY
-@end format
-@node top, Invoking, (dir), (dir)
+@node top, What Configure Does, (dir), (dir)
@top top
This file documents the configuration system used and distributed by
Cygnus Support.
-NOTE: support for a Cygnus experimental option, @code{-subdirs} is at
-least temporarily suspended. Most of the code is still in configure but
-the option is disabled. This document describes that feature, but those
-parts are prominently marked with NOTE's like this one. FIXME-soon
-
@menu
+* What Configure Does:: What Configure Does
* Invoking:: Invoking
* Using Configure:: Using Configure
-* What Configure Does:: What Configure Does
* Porting:: Porting with Configure
* Reference:: Gory details described
* Known Bugs:: Known Bugs
* Variables Index:: Variable Index
* Concept Index:: Concept Index
+ --- The Detailed Node Listing ---
+
+Using Configure
+
+* Install Locations:: Where to install things once they are built
+* Build Directories:: Where to build object files
+* Host:: Telling @code{configure} what will source will
+ be built
+* Target:: Telling @code{configure} what the source will
+ target
+* Local Conventions:: Adding information about local conventions
+
+Install Locations
+
+* prefix:: Changing the default install directory
+* exec_prefix:: How to separate host independent files
+ from host dependent files when
+ installing for multiple hosts
+* Install Details:: Full descriptions of all installation
+ subdirectories
+
+Porting with Configure
+
+* Programs:: Adding configure to new programs
+* Hosts and Targets:: Adding hosts and targets
+* Sites:: Adding site info
+
+Gory details described
+
+* Makefile Extensions:: Extensions to the @sc{gnu} coding standards
+* configure.in:: The format of the configure.in file
+* config.status:: config.status
+* Makefile Fragments:: Makefile Fragments
+
+The format of the @file{configure.in} file
+
+* Minimal:: A minimal configure.in
+* Configure Variables:: Variables available to configure.in
+* Declarations:: For each invocation
+* Per-host:: For each host
+* Per-target:: For each target
+* Post-target:: After each target
+* Example:: An example configure.in
@end menu
@end ifinfo
-@iftex
-@unnumbered Preface
-NOTE: support for a Cygnus experimental option, @code{-subdirs} is at
-least temporarily suspended. Most of the code is still in configure but
-the option is disabled. This document describes that feature, but those
-parts are prominently marked with NOTE's like this one. FIXME-soon
-@end iftex
+@node What Configure Does, Invoking, top, top
+@chapter What Configure Does
+
+@code{configure} prepares source directories for building working
+programs. A program cannot be built until its source has been
+configured. When configure runs, it does the following things.
+
+@table @emph
+@item Create build directories
+(see @ref{Build Directories}). When you run @code{configure} with the
+@code{-srcdir=} option, it uses the current directory as build
+directory, creating under it a directory tree that parallels the
+directory structure under the source directory. (See @ref{Invoking}).
+
+@item Generate makefiles
+A makefile template from the source directory, usually called
+@file{Makefile.in}, is copied to an output file in the build directory.
+The output file is usually named @file{Makefile}. @code{configure}
+places definitions for a number of standard makefile macros at the
+beginning of the output file. If @code{-prefix=} or @code{-exec_prefix}
+were specified on the @code{configure} command line, corresponding
+makefile variables are set accordingly. If host, target, or site
+specific makefile fragments exist, these are inserted into the output
+file. (See @ref{Makefiles, , , make, Makefiles}.)
+
+@item Generate @file{.gdbinit} If the source directory contains a
+@file{.gdbinit} file and the build directory is not the same as the
+source directory, a @file{.gdbinit} file is created in the build
+directory. This @file{.gdbinit} file contains @code{dir} commands and
+a @code{source} command, which will cause the @file{.gdbinit} file from
+the source directory to be read by GDB, and will allow GDB to find
+source files in either the source directory or the build directory.
+(see @ref{Command Files, , , gdb, Command Files}.)
+
+@item Make symbolic links
+Most directories have some symbolic links with generic names built
+pointing to specific files in the source directory. If the system where
+@code{configure} runs cannot support symbolic links, hard links are used
+instead.
+
+@item Miscellaneous
+If the source directory has special needs, they are handled by shell
+script fragments stored with the source. Usually there are no special
+needs, but sometimes they involve changes to the output makefile.
+
+@item Generate @file{config.status}
+@code{configure} creates a shell script named @file{config.status} in
+the build directory. This shell script, when run from the build
+directory, will reconfigure the build directory (but not its
+subdirectories). This is most often used to have a @code{Makefile} update
+itself automatically if a new source directory is available.
-@node Invoking, Using Configure, top, top
+@item Recursion
+If the source directory has subdirectories that should also be
+configured, @code{configure} is called for each.
+@end table
+
+@node Invoking, Using Configure, What Configure Does, top
@chapter Invoking
The usual way to invoke @code{configure} is as follows:
@example
configure @var{host}
@end example
-This asks @code{configure} to prepare the source to be compiled in a
+This prepares the source to be compiled in a
@var{host} environment with programs and files to be installed in
@file{/usr/local}.
-NOTE: support for multiple hosts is at least temporarily suspended.
-FIXME-soon
-
-If more than one host is specified on the command line, then
-configurations are created for each and @code{-subdirs} is assumed.
+@code{configure} prepares the source as you specify by selecting and
+using script and Makefile fragments prepared in advance, and stored with
+the source. @code{configure}'s command line options also allow you to
+specify other aspects of the source configuration:
@table @code
+@item -exec_prefix=@var{dir}
+Configure the source to install host dependent files in @var{dir}.
-@item -datadir=@var{dir}
-This option requests that the source be configured so that host
-independent files will be installed in @var{dir}.
-
-This option sets the @code{configure} variable @code{datadir}. If
-@code{datadir} is not empty, generated Makefiles will have their
-@code{datadir} variables set to this value. (See @xref{Install Details}.)
+This option sets the @code{configure} variable @code{exec_prefix}.
+Generated Makefiles will have their @code{exec_prefix} variables set to
+this value. (See @ref{Install Details}.)
@item -gas
-Notifies @code{configure} that the @sc{GNU} assembler is available on
-all specified hosts.
+Configure to use the @sc{GNU} assembler.
@item -help
-Displays a quick summary of how to invoke @code{configure}.
+Display a quick summary of how to invoke @code{configure}.
@item -host=@var{host}
FIXME-soon: I don't think this option should be documented.
-
-NOTE: support for this @code{-namesubdir=} is at least temporary
-suspended. FIXME-soon
-
-@item -namesubdir=@var{name}
-Asks that any subdirectories created by the @code{-subdirs} option be
-named @var{name}. Note that using multiple hosts with
-@code{-namesubdir=} isn't terribly useful.
+@c Then why does it exist? /Pesch 7jan92
@item -nfp
-Notifies @code{configure} that all of the specified targets have
-@emph{no floating point} units.
+@emph{No floating point} unit available on the target; configure to
+avoid dependencies on hardware floating point.
@item -norecursion
-Asks @code{configure} to configure only this directory. Any
-subdirectories are ignored. This is used by the executable shell script
-@file{config.status} to reconfigure the current directory.
-(see @xref{config.status}).
-
-@item -objdir=@var{dir}
-This option is no longer supported. Use @code{-srcdir=} instead.
+Configure only this directory; ignore any subdirectories. This is used
+by the executable shell script @file{config.status} to reconfigure the
+current directory. (see @ref{config.status}).
@item -prefix=@var{dir}
-This option requests that the source be configured so that programs and
-files will be installed in @var{dir}.
+Configure the source to install programs and files under directory
+@file{@var{dir}}.
+
+This option sets the @code{configure} variable @code{prefix}. Generated
+Makefiles will have their @code{prefix} variables set to this value.
+(See @ref{Install Details}.)
+
+@item -program_prefix=@var{string}
+Configure the source to install certain programs using @var{string} as a
+prefix. This applies to programs which might be used for cross-compilation,
+such as the compiler and the binutils, and also to programs which have the same
+name as a common Unix program, such as make.
+
+This option sets the @code{configure} variable @code{program_prefix}.
+Generated Makefiles will have their @code{program_prefix} variables set to this
+value. (See @ref{Install Details}.)
-This option sets the @code{configure} variable @code{prefix}. If
-@code{prefix} is not empty, generated Makefiles will have their
-@code{prefix} variables set to this value. (See @xref{Install Details}.)
+@item -program_suffix=@var{string}
+Configure the source to install certain programs using @var{string} as a
+suffix. This applies to programs which might be used for cross-compilation.
+
+@item -program_transform_name=@var{sed-pattern}
+Configure the source to install certain programs using the names that result
+from passing the usual name through @code{sed} invoked with @var{sed-pattern}.
+This option may be given multiple times; each @var{sed-pattern} will be applied
+in turn. This applies to programs which might be used for cross-compilation.
+
+This option sets the @code{configure} variable @code{program_transform_name}.
+Generated Makefiles will have their @code{program_transform_name} variables set
+to this value. (See @ref{Install Details}.)
@item -recurring
+@c Wouldn't it make more sense to call this "-quiet"? (FIXME).
This option is used internally by @code{configure} when recurring on
-subdirectories. It's sole purpose is to supress status output. It can
-be overriden with the @code{-verbose} option.
+subdirectories. Its sole purpose is to suppress status output. You can
+override this effect with the @code{-verbose} option.
@item -rm
-Asks @code{configure} to @emph{remove} a configuration rather than
-create one.
+@emph{Remove} the configuration specified by @var{host} and the other
+command-line options, rather than creating it.
@item -site=@var{site}
-Asks that Makefiles be generated using site specific Makefiles for
-@var{site}. (@xref{Makefile Fragments}.)
+Generate Makefiles using site specific Makefile fragments for
+@var{site}. See also @ref{Sites}.
@item -srcdir=@var{_dir}
-Tells @code{configure} that the sources are located in @var{dir}. The
+Build Makefiles to use the sources located in directory @file{@var{dir}}. The
build directory is assumed to be @file{.}.
-NOTE: support for this @code{-subdirs} is at least temporary suspended.
-FIXME-soon
-
-@item -subdirs
-Asks that configurations be placed in subdirectories named
-@file{H-@var{host}} of each build directory, for each host specified.
-If this configuration is not native, (@var{host} is not @var{target}),
-then he subdir will be named @file{X-@var{host}-@var{target}} instead.
-
-NOTE: support for multiple targets is at least temporarily suspended.
-FIXME-soon
-
@item -target=@var{target}
Requests that the sources be configured to target the @var{target}
-machine. If no targets are specified explicitly, the target is assumed
-to be the same as the host. If multiple targets are specified,
-configurations for each are created and @code{-subdirs} is assumed.
+machine. If no target is specified explicitly, the target is assumed
+to be the same as the host.
@item -tmpdir=@var{tmpdir}
-Sets the directory in which @code{configure} creates temporary files to
-@var{tmpdir}.
+Use the directory @var{tmpdir} for @code{configure}'s temporary files.
+The default is the value of the environment variable TMPDIR, or
+@file{/tmp} if the environment variable is not set.
@item -verbose
-@item -v
-Asks that @code{configure} print status lines for each directory
-configured. Normally, only the status lines for the current directory
-are printed.
+@itemx -v
+Print status lines for each directory configured. Normally, only the
+status lines for the initial working directory are printed.
@item -x
-Tells @code{configure} that @sc{MIT} style @sc{X11} header files and
-libraries are available on the host, even if they are not normally
-available.
-
+Use @sc{MIT} style @sc{X11} header files and libraries on the host, even
+if they are not normally available.
@end table
-@node Using Configure, What Configure Does, Invoking, top
+@node Using Configure, Porting, Invoking, top
@chapter Using Configure
-Configure prepares source directories in anticipation of building.
-Source cannot be built until it has been configured. The choices
-and options available at configuration time generally have valid
-defaults, but the defaults do not cover all cases. The choices
-available include:
+The choices and options available at configuration time
+generally have valid defaults, but the defaults do not cover all cases.
+The choices available include install locations, build directories,
+host, target, and local conventions.
@menu
* Install Locations:: Where to install things once they are built
@node Install Locations, Build Directories, Using Configure, Using Configure
@section Install Locations
-
@cindex Where to install
-Using the default configuration, @code{make install} will create a
+Using the default configuration, @code{make install} creates a
single tree of files, some of which are programs. The location of this
tree is determined by the value of the variable @code{prefix}. The
default value of @code{prefix} is @file{/usr/local}. This is
-probably correct for native tools installed on only one host.
+often correct for native tools installed on only one host.
@menu
-* prefix:: Changing the default install directory
-* datadir:: How to separate host independent files
+* prefix:: Changing the default install directory
+* exec_prefix:: How to separate host independent files
from host dependent files when
installing for multiple hosts
-* Install Details:: Full descriptions of all installation
+* Install Details:: Full descriptions of all installation
subdirectories
@end menu
-@node prefix, datadir, Install Locations, Install Locations
+@node prefix, exec_prefix, Install Locations, Install Locations
@subsection Changing the default install directory
-
@cindex Changing the default install directory
@cindex Prefix directory
In the default configuration, all files are installed in subdirectories
-of @file{/usr/local}. The actual location is determined by the value of
-the @code{configure} variable @code{prefix} which determines the
-value of the Makefile variable @code{prefix}.
+of @file{/usr/local}. The location is determined by the value of
+the @code{configure} variable @code{prefix}; in turn, this determines the
+value of the Makefile variable of the same name (@code{prefix}).
You can also set the value of the Makefile variable @code{prefix}
-explicitly each time you invoke @code{make} if you are so inclined, but
+explicitly each time you invoke @code{make} if you are so inclined; but
because many programs have this location compiled in, you must specify
-the @code{prefix} value precisely on each invocation of @code{make}
+the @code{prefix} value consistently on each invocation of @code{make},
or you will end up with a broken installation.
To make this easier, the value of the @code{configure} variable
@code{prefix} can be set on the command line to @code{configure}
-using the option @code{-prefix=}. (See @xref{prefix}).
+using the option @code{-prefix=}.
-@node datadir, Install Details, prefix, Install Locations
+@node exec_prefix, Install Details, prefix, Install Locations
@subsection Installing for multiple hosts
-
@cindex Configuring for multiple hosts
@cindex Sharing host independent files
-@cindex The datadir directory
+@cindex The @file{exec_prefix} directory
@cindex Installing host independent files
-Host independent files are installed in subdirectories of
-@file{/usr/local/lib}. The actual location is determined by the value
-of the @code{configure} variable @code{datadir} which determines
-the value of the Makefile variable @code{datadir}. By default, the
-value of @code{datadir} is @file{@code{prefix}/lib}. This makes
-single host installs simple, and simplifies changing the default
-location for the install tree, but doesn't allow for multiple hosts to
+By default, host dependent files are installed in subdirectories of
+@file{@var{exec_prefix}}. The location is determined by the value of the
+@code{configure} variable @code{exec_prefix}, which determines the value of
+the Makefile variable @code{exec_prefix}. This makes it simpler to install
+for a single host, and simplifies changing the default location for the
+install tree; but the default doesn't allow for multiple hosts to
effectively share host independent files.
To configure so that multiple hosts can share common files, use
something like:
@example
-configure @var{host1} -prefix=/usr/gnu/H-@var{host1} -datadir=/usr/gnu/H-independent
+configure @var{host1} -prefix=/usr/gnu -exec_prefix=/usr/gnu/H-host1
make all info install install-info clean
-configure @var{host2} -prefix=/usr/gnu/H-@var{host2} -datadir=/usr/gnu/H-independent
+
+configure @var{host2} -prefix=/usr/gnu -exec_prefix=/usr/gnu/H-host2
make all info install install-info
@end example
-The first line configures the source for @var{host1} in such a way that
-host specific programs will be placed in subdirectories of
-@file{/usr/gnu/H-@var{host1}} and host independent files will be placed
-in @file{/usr/gnu/H-independent}. (See @xref{datadir}.)
+The first line configures the source for @var{host1} to place host
+specific programs in subdirectories of @file{/usr/gnu/H-@var{host1}}.
The second line builds and installs all programs for @var{host1},
-including both host independent and host dependent files.
+including both host independent and host specific files.
-The third line reconfigures the source for @var{host2} in such a way
-that host specific programs will be placed in subdirectories of
-@file{/usr/gnu/H-@var{host2}} and host independent files will again be
-placed in @file{/usr/gnu/H-independent}.
+The third line reconfigures the source for @var{host2} to place host
+specific programs in subdirectories of @file{/usr/gnu/H-@var{host2}}.
The fourth line builds and installs all programs for @var{host2}. Host
-dependent files will be installed in new directories but the host
-independent files will be installed @emph{on top of} the host
+specific files are installed in new directories, but the host
+independent files are installed @emph{on top of} the host
independent files installed for @var{host1}. This results in a single
-copy of the host independent files suitable for use by both hosts.
-
-NOTE: support for -subdirsa and multiple hosts is at least temporarily
-suspended. FIXME-soon
-
-Previously this was:
+copy of the host independent files, suitable for use by both hosts.
-@example
-configure @var{host1} @var{host2} -prefix=/usr/gnu
-@end example
-
-@node Install Details, , datadir, Install Locations
+@node Install Details, , exec_prefix, Install Locations
@subsection Full descriptions of all installation subdirectories
-In any install, a number of standard directories are created. Their
-actual names are determined by Makefile variables. Some of the
+During any install, a number of standard directories are created. Their
+names are determined by Makefile variables. Some of the
defaults for Makefile variables can be changed at configure time using
command line options to @code{configure}. For more information on the
standard directories or the Makefile variables, please refer to
@cite{standards.text}.
-Note that @code{configure} does not create @code{srcdir} at any time.
-The directory @code{srcdir} is not an installation directory.
+Note that @code{configure} does not create the directory @code{srcdir}
+at any time. @code{srcdir} is not an installation directory.
-All makefile variables can be overridden on the command line to
-@code{make}. (See @xref{Overriding, Overriding Variables, Overriding
+You can override all makefile variables on the command line to
+@code{make}. (See @ref{Overriding, Overriding Variables, Overriding
Variables, make, Make}.) If you do so, you will need to specify the
-value precisely the same way for each invocation of @code{make} or you
+value precisely the same way for each invocation of @code{make}, or you
risk ending up with a broken installation. This is because many
programs have the locations of other programs or files compiled into
them. If you find yourself overriding any of the variables frequently,
-you should consider site dependent Makefile fragments. (See
-@xref{Makefile Fragments}.)
+you should consider site dependent Makefile fragments. See also
+@ref{Sites}.
-During @code{make install}, the following standard directories will be
-created and populated:
+During @code{make install}, a number of standard directories are
+created and populated. The following Makefile variables define them.
+Those whose defaults are set by corresponding @code{configure} variables
+are marked ``Makefile and configure''.
@vindex prefix
@defvr {Makefile and configure} prefix
-By default, the value of this variable determines the root of the
-installation tree. It may be overridden with the @code{-srcdir=}
-command line option to @code{configure}. (@xref{Invoking}.) The
-default value for @code{prefix} is @file{/usr/local}.
+The root of the installation tree. You can set
+its Makefile default with the @code{-prefix=} command line option to
+@code{configure}. (@ref{Invoking}.) The default value for
+@code{prefix} is @file{/usr/local}.
@end defvr
@vindex bindir
@defvr Makefile bindir
-The value of this variable names a directory intended to contain binary
-programs that users can run. The default value for @code{bindir}
-depends on @code{prefix} so @code{bindir} is normally changed
-only indirectly through @code{prefix}. The default value for
-@code{bindir} is @file{@code{prefix}/bin}.
+A directory for binary programs that users can run.
+The default value for @code{bindir} depends on @code{prefix};
+@code{bindir} is normally changed only indirectly through @code{prefix}.
+The default value for @code{bindir} is @file{$(prefix)/bin}.
@end defvr
-@vindex datadir
-@defvr {Makefile and configure} datadir
-The value of this variable names a directory intended to contain host
-independent files. The @code{configure} variable, which is used to set
-the default value of the Makefile variable, can be set at configure time
-using the @code{-datadir=} option to @code{configure}.
-(@xref{Invoking}.) The default value for @code{datadir} is
-@code{prefix}@file{/lib}.
+@vindex exec_prefix
+@defvr {Makefile and configure} exec_prefix
+A directory for host dependent files. You can specify the Makefile
+default value by using the @code{-exec_prefix=} option to @code{configure}.
+(See also @ref{Invoking}.) The default value for @code{exec_prefix} is
+@file{$(prefix)}.
@end defvr
@vindex libdir
@defvr Makefile libdir
-The value of this variable names a directory intended to hold libraries
-and support programs. The default value for @code{libdir}
-depends on @code{prefix} so @code{libdir} is normally changed
-only indirectly through @code{prefix}. The default value for
-@code{libdir} is @code{prefix}@file{/lib}.
+A directory for libraries and support programs. The default value for
+@code{libdir} depends on @code{prefix}; @code{libdir} is normally
+changed only indirectly through @code{prefix}. The default value for
+@code{libdir} is @file{$(prefix)/lib}.
@end defvr
@vindex mandir
@defvr Makefile mandir
-The value of this variable names a directory intended to hold @emph{man}
-format man pages. The default value for @code{mandir}
-depends on @code{prefix} so @code{mandir} is normally changed
-only indirectly through @code{prefix}. The default value for
-@code{mandir} is @code{datadir}@file{/man}.
+A directory for @code{man} format documentation (``man pages''). The
+default value for @code{mandir} depends on @code{prefix};
+@code{mandir} is normally changed only indirectly through @code{prefix}.
+The default value for @code{mandir} is @file{$(prefix)/man}.
@end defvr
@vindex man@var{N}dir
@defvr Makefile man@var{N}dir
-There are eight of these variables named @code{man1dir}, @code{man2dir},
-etc. They are intended to name the specific directories which hold the
-man pages of their respective sections. That is, @code{man1dir} holds
-@file{emacs.1}, the man page for the emacs program while @code{man5dir}
-holds the man page describing the @code{rcs} data file format, called
-@file{rcsfile.5}. The default value for @code{man@var{N}dir}
-depends on @code{prefix} so @code{man@var{N}dir} is normally changed
-only indirectly through @code{prefix}. The default value for
-@code{man@var{N}dir} is @code{mandir}@file{/man@var{N}}.
+There are eight variables named @code{man1dir}, @code{man2dir}, etc.
+They name the specific directories for each man page section. For
+example, @code{man1dir} holds @file{emacs.1} (the man page for the emacs
+program), while @code{man5dir} holds @file{rcsfile.5} (the man page
+describing the @code{rcs} data file format). The default value for any
+of the @code{man@var{N}dir} variables depends indirectly on
+@code{prefix}, and is normally changed only through @code{prefix}. The
+default value for @code{man@var{N}dir} is
+@file{$(mandir)/man@var{N}}.
@end defvr
@vindex manext
@defvr Makefile manext
-The makefile variable manext is not supported by the @code{configure}.
-The @sc{gnu} coding standards do not call for @code{man1ext},
-@code{man2ext}, so the intended use for @code{manext} is not clear.
-(See also @xref{Makefile Extensions}.)
+@emph{Not supported by @code{configure}}. The @sc{gnu} coding standards
+do not call for @code{man1ext}, @code{man2ext}, so the intended use for
+@code{manext} is apparently not parallel to @code{mandir}. Its use is
+not clear. (See also @ref{Makefile Extensions}.)
@end defvr
@vindex infodir
@defvr Makefile infodir
-The value of this variable names a directory intended to hold
-@emph{info} format documentation. The default value for @code{infodir}
-depends on @code{prefix} so @code{infodir} is normally changed
-only indirectly through @code{prefix}. The default value for
-@code{infodir} is @code{datadir}@file{/info}.
+A directory for @emph{info} format documentation. The default value for
+@code{infodir} depends indirectly on @code{prefix}; @code{infodir} is
+normally changed only through @code{prefix}. The default value for
+@code{infodir} is @file{$(prefix)/info}.
@end defvr
@vindex docdir
@defvr Makefile docdir
-The value of this variable names a directory intended to hold any
-documentation that is in a format other than @emph{info} or @emph{man}.
-The default value for @code{docdir} depends on @code{prefix} so
-@code{docdir} is normally changed only indirectly through @code{prefix}.
-The default value for @code{docdir} is @code{datadir}@file{/doc}. Note
-that this variable is an extension to the @sc{gnu} coding standards.
-(See also @xref{Makefile Extensions}.)
+A directory for any documentation that is in a format other than those
+used by @code{info} or @code{man}. The default value for @code{docdir}
+depends indirectly on @code{prefix}; @code{docdir} is normally changed only
+through @code{prefix}. The default value for @code{docdir}
+is @file{$(datadir)/doc}. @emph{This variable is an extension to
+the @sc{gnu} coding standards}. (See also @ref{Makefile Extensions}.)
@end defvr
@vindex includedir
@defvr Makefile includedir
-The value of this variable names a directory intended to hold the
-headers files that accompany the libraries installed in @code{libdir}.
-The default value for @code{includedir} depends on @code{prefix} so
-@code{includedir} is normally changed only indirectly through @code{prefix}. The default value for
-@code{includedir} is @code{prefix}@file{/include}.
+A directory for the header files accompanying the libraries installed in
+@code{libdir}. The default value for @code{includedir} depends on
+@code{prefix}; @code{includedir} is normally changed only indirectly
+through @code{prefix}. The default value for @code{includedir} is
+@file{$(prefix)/include}.
@end defvr
-
@node Build Directories, Host, Install Locations, Using Configure
@section Build Directories
-
@cindex Build directories
-@cindex objdir
+@kindex objdir
@cindex Object directories
-@cindex subdirs
+@kindex subdirs
@cindex Building for multiple hosts
@cindex Building for multiple targets
-Normally, @code{configure} builds @file{Makefile}'s and symbolic links
+Normally, @code{configure} builds a @file{Makefile} and symbolic links
in the same directory as the source files. This is the typical
-@sc{un*x} way to build programs but it has limitations. For instance,
+@sc{un*x} way to build programs, but it has limitations. For instance,
using this approach, you can only build for one host at a time.
-We refer to the directories in which @code{configure} builds
-@file{Makefile}'s as the @emph{build directories} or sometimes as
+We refer to the directories where @code{configure} builds a
+Makefile as the @emph{build directories} or sometimes as
@emph{objdir} because these are the directories in which @code{make}
will build object files, among other things.
The default build directory is the same as the source directory.
-
-You can change the build directory with a sequence like the following:
+You can use a different build directory with a sequence like the following:
@example
mkdir @var{builddir}
configure @var{host} -srcdir=@var{sourcedirectory}
@end example
-where @var{builddir} is the directory in which you wish to build,
+@noindent
+where @var{builddir} is the directory where you wish to build,
@var{host} is the host for which you want to build, and
@var{sourcedirectory} is the directory containing the source files.
If you were to do this twice with different values for @var{builddir}
and @var{host}, then you could @code{make} for both at the same time.
-NOTE: The rest of this section describes the @code{-subdirs} feature for
-which support is at least temporarily suspended. FIXME-soon.
-
-Another way to specify the build directory is with the @code{-subdirs}
-option. For example:
-
-@example
-configure @var{host} -subdirs
-@end example
-
-Using this option, @code{configure} will create a subdirectory named
-@file{H-@var{host}} to act as the build directory for each source
-directory.
-
-Since building for multiple hosts is so common, @code{configure}
-recognizes this situation as special. For example:
-
-@example
-configure @var{host1} @var{host2}
-@end example
-
-is precisely the same as:
-
-@example
-configure @var{host1} -subdirs
-configure @var{host2} -subdirs
-@end example
-
-That is, when configuring for multiple hosts or multiple targets,
-@code{-subdir} is assumed.
-
-When configuring for cross tools, that is, the host is not the target,
-as in:
-
-@example
-configure @var{host} +target=@var{targ} -subdirs
-@end example
-
-the subdirectories are named @file{X-@var{host}-@var{targ}}. This is
-especially useful when configuring for multiple targets.
-
-If both @code{-subdirs} and @code{-srcdir=} are given, a tree that
-parallels the source directory structure is created in the current
-directory, except that the current directory represents the source
-directory itself, and the subdirectories are created in this directory
-tree rather than in the source directories.
-
-NOTE: previously, -subdirs built two level subdirectories as
-./H-host/T-target, created ./H-host/Makefile for building across all
-targets, ./Makefile for building across all hosts, and ./config.status
-and ./H-host/config.status for rebuilding these Makefiles.
-
@node Host, Target, Build Directories, Using Configure
@section Host
-NOTE: support for multiple hosts is at least temporarily suspended.
-FIXME-soon.
-
The arguments to @code{configure} are @emph{hosts}. By @emph{host} we
mean the environment in which the source will be compiled. This need
-not necessarily be the same as the actual physical machine involved,
+not necessarily be the same as the physical machine involved,
although it usually is.
For example, if some obscure machine running an operating system other
-than @sc{un*x} actually had the @sc{gnu} @sc{posix} emulation libraries
+than @sc{un*x} had the @sc{gnu} @sc{posix} emulation libraries
available, it would be possible to configure most @sc{gnu} source for a
@sc{posix} system and build it on the obscure host.
-For more on this topic, see @xref{Host Environments, , cfg-paper, On
-Configuring Development Tools}.
+For more on this topic, see @ref{Host Environments, , Host Environments,
+cfg-paper, On Configuring Development Tools}.
@node Target, Local Conventions, Host, Using Configure
@section Target
-For building native development tools, or most of the other tools in the
-@sc{gnu} collection, you need not worry about the target. The
-@emph{target} of a configuration defaults to the same as the
-@emph{host}.
+For building native development tools, or most of the other @sc{gnu}
+tools, you need not worry about the target. The @emph{target} of a
+configuration defaults to the same as the @emph{host}.
-For building cross development tools, please see @xref{Building
-Development Environments, , cfg-paper, On Configuring Development
-Tools}.
+For building cross development tools, please see @ref{Building
+Development Environments, , Building Development Environments,
+cfg-paper, On Configuring Development Tools}.
@node Local Conventions, , Target, Using Configure
@section Local Conventions
-If you find that a tool does not get configured to your liking or that
-@code{configure}'s conventions are not your local conventions, you
-should probably consider site specific Makefile fragments. (see
-@xref{Makefile Fragments})
+If you find that a tool does not get configured to your liking, or if
+@code{configure}'s conventions differ from your local conventions, you
+should probably consider site specific Makefile fragments. See also
+@ref{Sites}.
These are probably not the right choice for options that can be set from
the @code{configure} command line or for differences that are host or
target dependent.
-
-@node What Configure Does, Porting, Using Configure, top
-@chapter What Configure Does
-
-When configure runs, it does the following things for each source
-directory for each host and target combination.
-
-NOTE: support for multiple hosts and targets is at least temporarily
-suspended.
-
-@itemize @bullet
-
-@item Create Build Directories
-(see @xref{Build Directories}) When @code{configure} is run with the
-@code{-srcdir=} option, a directory tree is created that parallels the
-directory structure of the source directory except that the current
-directory is treated as the build directory for the source directory
-proper. (see @xref{Invoking}).
-
-NOTE: support for @code{-subdirs} is at least temporarily suspended.
-
-When @code{configure} is run with the @code{-subdirs} option, a build
-directory is created in each source directory.
-
-If both @code{-subdirs} and @code{-srcdir=} are given, a tree that
-parallels the source directory structure is created in the current
-directory, except that the current directory represents the source
-directory itself, and the subdirectories are created in this directory
-tree rather than in the source directories.
-
-@item Generate Makefiles
-A makefile template, usually called @file{Makefile.in} from the source
-directory is copied to an output file in the build directory. The
-output file is usually named @file{Makefile}. A number of makefile
-macros are prepended to the output file. If @code{-prefix=} or
-@code{-datadir=} were specified on the @code{configure} command line,
-then the makefile variables are set accordingly. If host, target, or
-site, specific makefile fragments exist, they are inserted into the
-output file. (see @xref{Makefiles, , , make, Makefiles}.)
-
-@item Generate .gdbinit
-If the source directory contains a .gdbinit file and the build directory
-is different from the source directory, a .gdbinit file is created in
-the build directory. (see @xref{Command Files, , , gdb, Command Files}.)
-
-@item Make Symbolic Links
-Most directories have some symbolic links with generic names built
-pointing to specific files in the source directory. If the system on
-which @code{configure} is run cannot support symbolic links, then hard
-links are used instead.
-
-@item Miscellaneous
-If the source directory has special needs, they are handled. Usually
-there are none, but sometimes they involve changes to the output
-makefile.
-
-@item Generate config.status
-A shell script named @file{config.status} is created in the build
-directory. This shell script, when run from the build directory, will
-reconfigure the build directory except that subdirectories are not
-reconfigured. This is most often used by @code{make} to rebuild the
-output makefile. (see @xref{Top, , , bash}.)
-
-@item Recursion
-If the source directory has subdirectories that should also be
-configured, then @code{configure} is called for each.
-
-@end itemize
-
-@node Porting, Reference, What Configure Does, top
+@node Porting, Reference, Using Configure, top
@chapter Porting with Configure
-
@cindex Porting
-This section explains briefly how to port configure for:
+
+This section explains how to add programs, host and target configuration
+names, and site-specific information to Cygnus configure.
@menu
-* Programs:: Adding configure to existing programs
-* Hosts:: Adding hosts to a program that uses Cygnus configure
-* Targets:: Adding targets to a program that uses Cygnus configure
-* Sites:: Adding site info to programs that use Cygnus configure
+* Programs:: Adding configure to new programs
+* Hosts and Targets:: Adding hosts and targets
+* Sites:: Adding site info
@end menu
-@node Programs, Hosts, Porting, Porting
-@section Adding Configure To Existing Programs
+@node Programs, Hosts and Targets, Porting, Porting
+@section Adding Configure To New Programs
If you are writing a new program, you probably shouldn't worry about
porting issues or configure until it is running reasonably on some host.
Then refer back to this section.
If the program in question currently has a configure script that meets
-the criterion set out by @cite{standards.text}, please do not add Cygnus
+the criteria set out by @cite{standards.text}, please do not add Cygnus
configure. It should be possible to add this program without change to
a Cygnus configure style source tree.
If the program is not target dependent, please consider using
-@code{autoconf} instead of Cygnus configure. Autoconf will soon be
-available from the @sc{fsf}.
+@code{autoconf} instead of Cygnus configure. @code{autoconf} will
+be available soon from the @sc{fsf}.
-To add Cygnus configure to an existing program, do the following.
+To add Cygnus configure to an existing program, do the following:
@table @asis
-
-@item Bring the Makefile up to the standard
+@item Make sure the Makefile conforms to @sc{gnu} standard
The coding standard for @sc{gnu} Makefiles is described in
@cite{standards.text}.
@item Add Cygnus extensions to the Makefile
-There are described in @xref{Makefile Extensions}.
+These are described in @ref{Makefile Extensions}.
@item Move host support from Makefile to fragments
This usually involves finding sections of the Makefile that say things
like ``uncomment these lines for host foo'' and moving them to a new
-file call @file{./config/mh-foo}. For more on this, see @xref{Makefile Fragments}.
+file called @file{./config/mh-foo}. For more information, see @ref{Hosts
+and Targets}.
+
+@item Choose defaults
+If the program has compile time options that determine the way the
+program should behave, chose reasonable defaults and make these Makefile
+variables. Be sure the variables are assigned their default values
+before the @code{####} line so that site specific Makefile fragments can
+override them (@pxref{Makefile Extensions,,Extensions to the @sc{gnu}
+coding standards}).
@item Locate configuration files
If there is configuration information in header files or source files,
separate it in such a way that the files have a generic name. Then move
-the specific instances of those files into @file{./config}.
+the specific instances of those files into the @file{./config}
+directory.
@item Separate host and target information
-Some programs already have this information separated. If not, you will
-need to do so. Host specific information is the information needed to
-compile the program. Target specific information it information on the
+Some programs already have this information separated. If yours does
+not, you will need to separate these two kinds of configuration
+information. @dfn{Host specific} information is the information needed to
+compile the program. @dfn{Target specific} information is information on the
format of data files that the program will read or write. This
information should live in separate files in the @file{./config}
directory with names that reflect the configuration for which they are
wrong. This is often simpler than combing through all of the source
code.
-@item Write configure.in
+@item Write @code{configure.in}
Usually this involves writing shell script fragments to map from
canonical configuration names into the names of the configuration files.
These files will then be linked at configure time from the specific
instances of those files in @file{./config} to file in the build
-directory with more generic names. (see also @xref{Build Directories}).
-The format of configure.in is described in @xref{configure.in}.
-
-@item Rename the Makefile to Makefile.in
+directory with more generic names. (see also @ref{Build Directories}).
+The format of configure.in is described in @ref{configure.in}.
+@item Rename @file{Makefile} to @file{Makefile.in}
@end table
-At this point you should have a program that can be configured by Cygnus
-configure.
+At this point you should have a program that can be configured using
+Cygnus @code{configure}.
+
+@node Hosts and Targets, Sites, Programs, Porting
+@section Adding hosts and targets
+
+To add a host or target to a program that already uses Cygnus
+configure, do the following.
+
+@itemize @bullet
+
+@item
+Make sure the new configuration name is represented in
+@file{config.sub}. If not, add it. For more details, see the comments
+in the shell script @file{config.sub}.
+
+@item
+If you are adding a host configuration, look in @file{configure.in}, in
+the per-host section. Make sure that your configuration name is
+represented in the mapping from host configuration names to
+configuration files. If not, add it. Also see @ref{configure.in}.
+
+@item
+If you are adding a target configuration, look in @file{configure.in},
+in the per-target section. Make sure that your configuration name is
+represented in the mapping from target configuration names to
+configuration files. If not, add it. Also see @ref{configure.in}.
+
+@item
+Look in @file{configure.in} for the variables @samp{files},
+@samp{links}, @samp{host_makefile_frag}, and
+@samp{target_makefile_frag}. The values assigned to these variables are
+the names of the configuration files, relative to @code{srcdir} that the
+program uses. Make sure that copies of the files exist for your host.
+If not, create them. See also @ref{Configure Variables}.
+@end itemize
+
+This should be enough to configure for a new host or target
+configuration name. Getting the program to compile and run properly
+remains the hard work of the port.
+
+@node Sites, , Hosts and Targets, Porting
+@section Adding site info
+
+If some of the Makefile defaults are not right for your site, you can
+build site specific Makefile fragments. To do this, do the following.
+
+@itemize @bullet
-@node Hosts, Targets, Programs, Porting
-@section Adding hosts to a program that uses Cygnus configure
+@item
+Choose a name for your site. It must be less than eleven characters for
+now.
-Coming soon. FIXME-now.
+@item
+If the program source does not have a @file{./config} directory, create it.
-@node Targets, Sites, Hosts, Porting
-@section Adding targets to a program that uses Cygnus configure
+@item
+Create a file called @file{./config/ms-@var{site}} where @var{site} is
+the name of your site. In it, set whatever Makefile variables you need
+to override to match your site's conventions.
-Coming soon. FIXME-now.
+@item
+Configure the program with:
-@node Sites, , Targets, Porting
-@section Adding site info to programs that use Cygnus configure
+@example
+configure @dots{} +site=@var{site}
+@end example
-Coming soon. FIXME-now.
+@end itemize
@node Reference, Known Bugs, Porting, top
@chapter Gory details described
for Cygnus configure to work properly.
@itemize @bullet
-
@item
The Makefile must contain exactly one line starting with @code{####}.
This line should follow any default macro definitions but precede any
rules. Host, target, and site specific Makefile fragments will be
inserted immediately after this line. If the line is missing, the
fragments will not be inserted.
-
@end itemize
Cygnus adds the following targets to our Makefiles. Their existence is
-not required for Cygnus configure but are documented here for
+not required for Cygnus configure, but they are documented here for
completeness.
@table @code
-
+@kindex info
@item info
Build all info files from texinfo source.
+@kindex install-info
@item install-info
Install all info files.
+@kindex clean-info
@item clean-info
Remove all info files and any intermediate files that can be generated
from texinfo source.
+@kindex stage1
@item stage1
-@item stage2
-@item stage3
-@item stage4
-@item de-stage1
-@item de-stage2
-@item de-stage3
-@item de-stage4
-@item bootstrap
-@item comparison
-@item Makefile
+@kindex stage2
+@itemx stage2
+@kindex stage3
+@itemx stage3
+@kindex stage4
+@itemx stage4
+@kindex de-stage1
+@itemx de-stage1
+@kindex de-stage2
+@itemx de-stage2
+@kindex de-stage3
+@itemx de-stage3
+@kindex de-stage4
+@itemx de-stage4
+@kindex bootstrap
+@itemx bootstrap
+@kindex comparison
+@itemx comparison
+@kindex Makefile
+@itemx Makefile
These targets are in transition and may be removed shortly.
-
@end table
In addition, the following Makefile targets have revised semantics:
@table @code
-
+@kindex install
@item install
Should @emph{not} depend on the target @code{all}. If the program is
-not already built, @code{make install} should fail. This allows
-programs to be installed even when @code{make} would otherwise determine
+not already built, @code{make install} should fail. This allows you
+to install programs even when @code{make} would otherwise determine
them to be out of date. This can happen when the result of a @code{make
all} is transported via tape to another machine for installation as
well as in a number of other cases.
+@kindex clean
@item clean
Should remove any file that can be regenerated by the Makefile,
excepting only the Makefile itself, and any links created by configure.
@noindent
will fail because of intermediate files intended for @var{host1}.
-
@end table
-Cygnus adds the following macros to all Makefile.in's. Their presence
-is not required for Cygnus configure.
+Cygnus adds the following macros to all @file{Makefile.in} files, but
+you are not required to use them to run Cygnus configure.
@table @code
-
+@kindex docdir
@item docdir
The directory in which to install any documentation that is not either a
man page or an info file. For man pages, see mandir, for info, see
infodir.
+@kindex includedir
@item includedir
The directory in which to install any headers files that should be made
available to users. This is distinct from the @code{gcc} include
directory which is intended for @code{gcc} only. Files in
@code{includedir} may be used by @code{cc} as well.
-
@end table
-In addition, the following macros have revised semantics.
+In addition, the following macros have revised semantics. Most of them
+describe installation directories; see also @ref{Install Details,,Full
+description of all installation subdirectories}.
@table @code
+@kindex manext
@item manext
-is not used. The intended usage is not clear. For example, if I have a
+is not used. The intended usage is not clear. For example, if you have a
@file{foo.man} and a @file{bar.man}, and @file{foo.man} is destined for
@file{/usr/local/lib/man/man1/foo.1} while @file{bar.man} is destined
-for @file{/usr/local/lib/man/man5/bar.5}, then to what should the value
-of @code{manext} be set?
+for @file{/usr/local/lib/man/man5/bar.5}, then what is the desired value
+of @code{manext}?
+@kindex datadir
@item datadir
-is used for @emph{all} host independent files. This makes it possible
-to share host independent files across multiple hosts without ersorting
-to symlinks or multiple mount points. This also makes it possible
-build an install tree that contains multiple host binaries, write
-the binaries to tape, and extract any of the hosts without extracting
-the others.
+is used for host independent data files.
+@kindex mandir
@item mandir
-man pages are host independent so the default path for @code{mandir}
-depends on @code{datadir}.
+The default path for @code{mandir} depends on @code{prefix}.
+@kindex infodir
@item infodir
-info files are host independent so the default path for @code{infodir}
-depends on @code{datadir}.
+The default path for @code{infodir} depends on @code{prefix}.
+@kindex BISON
@item BISON
-is assumed to have a yacc calling convention. To actually use
+is assumed to have a @code{yacc} calling convention. To use
@code{bison}, use @code{BISON=bison -y}.
-
@end table
-Cygnus also adds the following restrictions on our Makefiles.
+Cygnus Makefiles also conform to one additional restriction:
@itemize @bullet
-
@item
When libraries are installed, the line containing the call to
@code{INSTALL_DATA} should always be followed by a line containing a
-call to @code{RANLIB}. This is to accomodate systems that use
-@code{ranlib}. Systems that do not use ranlib can set @code{RANLIB} to
-@code{echo} in a host specific Makefile fragment.
-
+call to @code{RANLIB} on the installed library. This is to accomodate
+systems that use @code{ranlib}. Systems that do not use @code{ranlib}
+can set @code{RANLIB} to @code{echo} in a host specific Makefile
+fragment.
@end itemize
@node configure.in, config.status, Makefile Extensions, Reference
-@section The format of the configure.in file
-
-@cindex configure.in
-
-A configure.in file for Cygnus configure consists of a declarations
-section, followed by a per-host section, followed by a per-target
-section, optionally followed by a post-target section. Each section is
-a shell script fragment sourced by configure at the appropriate time.
-The interface between configure and the shell fragments is through a set
-of shell variables. All sections are sourced in the build directory.
+@section The format of the @file{configure.in} file
+@kindex configure.in
+
+A @file{configure.in} file for Cygnus configure consists of a
+@dfn{per-invocation} section, followed by a @dfn{per-host} section,
+followed by a @dfn{per-target} section, optionally followed by a
+@dfn{post-target} section. Each section is a shell script fragment,
+which is sourced by the configure shell script at an appropriate time.
+Values are passed among configure and the shell fragments through a
+set of shell variables. When each section is being interpreted
+(sourced) by the shell, the shell's current directory is the build
+directory, and any files created by the section (or referred to by the
+section) will be relative to the build directory. To reference files
+in other places (such as the source directory), prepend a shell
+variable such as @code{srcdir} to the desired file name.
+
+@cindex Per-invocation section
+The beginning of the @file{configure.in} file begins the per-invocation
+section.
+@cindex Per-host section
A line beginning with @code{# Per-host:} begins the per-host section.
+@cindex Per-target section
A line beginning with @code{# Per-target:} begins the per-target
section.
-If it exists, the post-target section begins with @code{# Per-target:}
-on a line by itself.
+@cindex Post-target section
+If it exists, the post-target section begins with @code{# Per-target:}.
@menu
* Minimal:: A minimal configure.in
* Configure Variables:: Variables available to configure.in
-* Declarations:: Per invocation
-* Per-host:: On a host basis
-* Per-target:: On a target basis
+* Declarations:: For each invocation
+* Per-host:: For each host
+* Per-target:: For each target
* Post-target:: After each target
* Example:: An example configure.in
@end menu
@node Minimal, Configure Variables, configure.in, configure.in
-@subsection A minimal configure.in
+@subsection A minimal @file{configure.in}
-@cindex Minimal configure.in example
+@cindex Minimal @file{configure.in} example
A minimal @file{configure.in} consists of four lines.
@example
# Per-target:
@end example
-The per-host and per-target lines divide the file into the three
-required sections. The srctrigger line names a file. configure checks
-to see that this file exists in the source directory before
-configuring. If the srctrigger file does not exist, configure
-uses the value of srcname to print an error message about not finding
-the source.
+The @samp{Per-host} and @samp{Per-target} lines divide the file into the
+three required sections. The @samp{srctrigger} line names a file.
+@code{configure} checks to see that this file exists in the source
+directory before configuring. If the @samp{srctrigger} file does not
+exist, @code{configure} uses the value of @samp{srcname} to print an
+error message about not finding the source.
+This particular example uses no links, and only the default host,
+target, and site specific Makefile fragments if they exist.
@node Configure Variables, Declarations, Minimal, configure.in
@subsection Variables available to configure.in
-@cindex Configure.in interface
+@cindex @file{configure.in} interface
-The following variables are available to the shell fragments in
-@file{configure.in}.
+The following variables pass information between the standard parts of
+@code{configure} and the shell-script fragments in @file{configure.in}:
@defvar{srctrigger}
Contains the name of a source file that is expected to live in the
-source directory. This is usually set in the declations section of
-@file{configure.in}. Configure tests to see that this file exists. If
-the file does not exist, configure prints an error message. This is
-used as a sanity check that configure.in matches the source directory.
+source directory. You must usually set this in the per-invocation
+section of @file{configure.in}. Configure tests to see that this file
+exists. If the file does not exist, configure prints an error message.
+This is used as a sanity check that configure.in matches the source
+directory.
@end defvar
@defvar{srcname}
-Contains the name of the source contained in the source directory. This
-is usually set in the declarations section of @file{configure.in}. If
-the file named in @code{srctrigger} does not exist, configure uses the
-value of this variable when it prints the error message.
+Contains the name of the source collection contained in the source
+directory. You must usually set this in the per-invocation section of
+@file{configure.in}. If the file named in @code{srctrigger} does not
+exist, configure uses the value of this variable when it prints the
+error message.
@end defvar
@defvar{configdirs}
-Contains the names of any subdirectories on which configure should
-recur. This is usually set in the declarations section of
-@file{configure.in}. If @file{Makefile.in} contains a line starting
-with @code{SUBDIRS =}, then it will be replaced with an assignment to
-@code{SUBDIRS} using the value of @code{configdirs}. This can be used
-to determine which directories to configure and build depending on the
-host and target configurations.
+Contains the names of any subdirectories where @code{configure} should
+recur. You must usually set this in the per-invocation section of
+@file{configure.in}.
+If @file{Makefile.in} contains a line starting with @code{SUBDIRS =},
+then it will be replaced with an assignment to @code{SUBDIRS} using
+the value of @code{configdirs} (if @code{subdirs} is empty). This can
+be used to determine which directories to configure and build depending
+on the host and target configurations.
+@c Most other matching makefile/config vars use the same name. Why not
+@c this? (FIXME).
+@c Can we get rid of SUBDIRS-substitution? It doesn't work well with subdirs.
+Use @code{configdirs} (instead of the @code{subdirs} variable
+described below) if you want to be able to partition the
+sub-directories, or use independent Makefile fragments.
+Each sub-directory can be independent, and independently re-configured.
@end defvar
-NOTE: support for multiple targets is currently suspended.
-
-@defvar{target_dependent}
-If this variable is not empty and @code{-subdirs} is in effect then
-configure will create separate build directories for each target. This
-is usually set in the declarations section of @file{configure.in}. The
-default is to assume that a directory is target independent, create only
-one real directory with symlinks from the other names. This means that
-a target independent directory will be built exactly once regardless of
-how many targets are being built.
+@defvar{subdirs}
+Contains the names of any subdirectories where @code{configure} should
+create a @code{Makefile} (in addition to the current directory),
+@emph{without} recursively running @code{configure}.
+Use @code{subdirs} (instead of the @code{configdirs} variable
+described above) if you want to configure all of the directories
+as a unit. Since there is a single invocation of @code{configure}
+that configures many directories, all the directories can use the
+same Makefile fragments, and the same @code{configure.in}.
@end defvar
@defvar{host}
-Contains the actual name that the user entered for the host. Since many
-things that the user could enter would map to the same canonical triple,
-this variable is innappropriate to use for picking available
-configurations. For that, use @code{host_cpu}, @code{host_vendor},
-and/or @code{host_os}. This variable is useful, however, for error
-messages.
+Contains the full configuration name (generated by the script
+@file{config.sub} from the name that the user entered) for the host.
+This is a three-part name of the form
+
+@example
+@var{cpu}-@var{vendor}-@var{os}
+@end example
+
+@noindent
+There are separate variables @code{host_cpu}, @code{host_vendor}, and
+@code{host_os} that you can use to test each of the three parts; this
+variable is useful, however, for error messages, and for testing
+combinations of the three components.
@end defvar
@defvar{host_cpu}
host as returned by @file{config.sub}. This is usually used to
distinguish betwen the numerous variations between @emph{common}
operating systems.
+@c "@emph{common} OS" doesn't convey much to me. Is this meant to cover
+@c cases like Unix, widespread but with many variations?
@end defvar
@defvar{host_os}
@end defvar
@defvar{target}
-Contains the actual name that the user entered for the target. Since
-many things that the user could enter would map to the same canonical
-triple, this variable is innappropriate to use for picking available
-configurations. For that, use @code{target_cpu}, @code{target_vendor},
-and/or @code{target_os}. This variable is useful, however, for error
-messages.
+Contains the full configuration name (generated by the script
+@file{config.sub} from the name that the user entered) for the target.
+This is a three-part name of the form
+
+@example
+@var{cpu}-@var{vendor}-@var{os}
+@end example
+
+@noindent
+There are separate variables @code{target_cpu}, @code{target_vendor}, and
+@code{target_os} that you can use to test each of the three parts; this
+variable is useful, however, for error messages, and for testing
+combinations of the three components.
@end defvar
@defvar{target_cpu}
linker, etc. Most programs will not need the @code{target} variables at
all, but this one could conceivably be used to build a program, for
instance, that operated on binary data files whose byte order or
-alignment are other than that of the system on which the program is
-running.
+alignment differ from the system where the program is running.
@end defvar
@defvar{target_vendor}
target as returned by @file{config.sub}. This is usually used to
distinguish betwen the numerous variations between @emph{common}
operating systems or object file formats. Sometimes it is used to
-switch between different flavors of users interfaces.
+switch between different flavors of user interfaces.
+@c above query re "@emph{common} OS" applies here too
@end defvar
@defvar{target_os}
interface the tool should provide.
@end defvar
-@defvar{nfp}
-Is set to @code{true} if the user invoked configure with the @code{-nfp}
+@defvar{floating_point}
+Is set to @code{no} if the user invoked configure with the @code{-nfp}
command line option, otherwise it is empty. This is a request to target
-a machine with @emph{no floating point} unit, even if the machine
-ordinarily has a floating point unit available. This option has no
+machines with @emph{no floating point} unit, even if the targets
+ordinarily have floating point units available. This option has no
negation.
@end defvar
@defvar{gas}
Is set to @code{true} if the user invoked configure with the @code{-gas}
command line option, otherwise it is empty. This is a request to assume
-that the target machine has gas available even if it ordinarily does
-not. The converse option, @code{-no-gas} is not available.
+that all target machines have @sc{gas} available even if they ordinarily do
+not. The converse option @samp{-no-gas} is not available.
@end defvar
@defvar{x}
Is set to @code{true} if the user invoked configure with the @code{-x}
command line option, otherwise it is empty. This is a request to assume
-that @sc{mit x11} compatible headers files and libraries are available,
-regardless of what is normally available on this host.
+that @sc{mit x11} compatible headers files and libraries are available
+on all hosts, regardless of what is normally available on them.
@end defvar
@defvar{srcdir}
Is set to the name of the directory containing the source for this
program. This will be different from @file{.} if the user has specified
-either the @code{-srcdir=} or the @code{-subdirs} options. Note that
-@code{srcdir} is not necessarily an absolute path.
+the @code{-srcdir=} option. Note that @code{srcdir} is not necessarily
+an absolute path.
@end defvar
@defvar{host_makefile_frag}
-Is set to a file name representing to the default Makefile fragment for
-this host. It may be set in @file{configure.in} to overide this
-default.
+If set by @file{configure.in}, this variable should be the name a file,
+relative to @code{srcdir} to be included in the resulting Makefile. If
+the named file does not exist, @code{configure} will print a warning
+message. This variable is not set by @code{configure}.
@end defvar
@defvar{target_makefile_frag}
-Is set to a file name representing to the default Makefile fragment for
-this target. It may be set in @file{configure.in} to overide this
-default.
+If set by @file{configure.in}, this variable should be the name of a
+file, relative to @code{srcdir}, to be included in the resulting
+Makefile. If the named file does not exist, @code{configure} will print
+a warning message. This variable is not set by @code{configure}.
@end defvar
-@defvar{site_makefile_frag}
+@defvar{site_makefile_frag}
Is set to a file name representing to the default Makefile fragment for
-this host. It may be set in @file{configure.in} to overide this
+this host. It may be set in @file{configure.in} to override this
default. Normally @code{site_makefile_frag} is empty, but will have a
-value if the user specified @code{-site=} on the command line. This
-variable should probably not be overridden.
+value if the user specified @code{-site=} on the command line. It is
+probably not a good idea to override this variable from
+@file{configure.in}, since that may defeat the @code{configure} user's
+intentions.
@end defvar
@defvar{Makefile}
@defvar{files}
If this variable is non-empty following the @code{per-target:} section,
-then each word in it's value will be the target of a symbolic link named
-in the @code{links} variable.
+then each word in its value will be the target of a symbolic link named
+in the corresponding word from the @code{links} variable.
@end defvar
@defvar{links}
If the @code{files} variable is non-empty following the
-@code{per-target:} section, then symbolic links will be created with the
-first word of links pointing to the first word of files, the second word
-of links pointing to the second word of files, and so on.
+@code{per-target:} section, then @code{configure} creates symbolic links
+with the first word of @code{links} pointing to the first word of
+@code{files}, the second word of @code{links} pointing to the second
+word of @code{files}, and so on.
@end defvar
-
@node Declarations, Per-host, Configure Variables, configure.in
-@subsection Per invocation
+@subsection For each invocation
@cindex Declarations section
-Everything from the start of @file{configure.in} up to a line beginning
-with @code{# Per-host:} is sourced by configure as a shell script
-fragment immediately after parsing command line arguments. The
-variables @code{srctrigger} and @code{srcname} @emph{must} be set here.
+@code{configure} sources the entire shell script fragment from the start
+of @file{configure.in} up to a line beginning with @samp{# Per-host:}
+immediately after parsing command line arguments. The variables
+@code{srctrigger} and @code{srcname} @emph{must} be set here.
-Some other things you might want to set here are the variables
-@code{configdirs} or @code{target_dependent}. FIXME-soon.
-target_dependent isn't useful without multiple targets.
+You might also want to set the variable @code{configdirs} here.
@node Per-host, Per-target, Declarations, configure.in
-@subsection On a host basis
+@subsection For each host
+@cindex per-host section
+@cindex host shell-script fragment
-@cindex Per-host section
-@cindex Host basis
-The per-host section of @file{configure.in} starts with a line beginning
-with @code{# Per-host:} and ends before a line beginning with with
-@code{# Per-target:}. Configure sources the per-host section once for
+The per-host section of @file{configure.in} starts with the line that begins
+with @samp{# Per-host:} and ends before a line beginning with
+@samp{# Per-target:}. @code{configure} sources the per-host section once for
each host.
This section usually contains a big case statement using the variables
-@code{host_cpu}, @code{host_vendor}, and @code{host_os} to determine
-appropriate values for @code{host_makefile_frag} and @code{files},
-although @code{files} is not usually set here. Usually, it is set
+@samp{host_cpu}, @samp{host_vendor}, and @samp{host_os} to determine
+appropriate values for @samp{host_makefile_frag} and @samp{files},
+although @samp{files} is not usually set here. Usually, it is set
at the end of the per-target section after determining the names of the
target specific configuration files.
@node Per-target, Post-target, Per-host, configure.in
-@subsection On a target basis
-
-@cindex Per-target section
-@cindex Target basis
-
-The per-target section of @file{configure.in} starts with a line
-beginning with @code{# Per-target:} and ends before a line beginning
-with @code{# Post-target:} if it exists. Otherwise the per-target
-section extends to the end of the file. Configure sources the
-per-target section once for each target before building any files,
+@subsection For each target
+@cindex per-target section
+@cindex target shell-script fragment
+
+The per-target section of @file{configure.in} starts with the line that
+begins with @samp{# Per-target:} and ends before the line that begins
+with @samp{# Post-target:}, if there is such a line. Otherwise the
+per-target section extends to the end of the file. @code{configure} sources
+the per-target section once for each target before building any files,
directories, or links.
-This section usually contains a big case statement using the variables
-@code{target_cpu}, @code{target_vendor}, and @code{target_os} to determine
-appropriate values for @code{target_makefile_frag} and @code{files}.
+This section usually contains a big case statement using the variables called
+@samp{target_cpu}, @samp{target_vendor}, and @samp{target_os} to determine
+appropriate values for @samp{target_makefile_frag} and @samp{files}.
The last lines in the per-target section normally set the variables
@code{files} and @code{links}.
The post-target section is optional. If it exists, the post-target
section starts with a line beginning with @code{# Post-target:} and
-extends to the end of the file. If it exists, configure sources this
+extends to the end of the file. If it exists, @code{configure} sources this
section once for each target after building all files, directories, or
links.
-This section seldom exists but can be used to munge the configure
-generated Makefile.
+This section is seldom needed, but you can use it to edit the Makefile
+generated by @code{configure}.
@node Example, , Post-target, configure.in
-@subsection An example configure.in
+@subsection An example @file{configure.in}
+@cindex example @file{configure.in}
+@cindex sample @file{configure.in}
+@cindex Bison @file{configure.in}
-@cindex Example configure.in
-@cindex Bison configure.in
-Here is a small example configure.in.
+Here is a small example of a @file{configure.in} file.
@example
-# This file is a shell script fragment that supplies the information
-# necessary to tailor a template configure script into the configure
-# script appropriate for this directory. For more information, check
-# any existing configure script.
+# This file is a collection of shell script fragments used to tailor
+# a template configure script as appropriate for this directory.
+# For more information, see configure.texi.
configdirs=
srctrigger=warshall.c
srcname="bison"
# per-host:
-case "${host_os}" in
+case "$@{host_os@}" in
m88kbcs)
host_makefile_frag=config/mh-delta88
;;
@end example
@node config.status, Makefile Fragments, configure.in, Reference
-@section config.status
+@section @code{config.status}
-@cindex config.status
+@kindex config.status
-Coming soon. FIXME-soon.
+The final step in configuring a directory is to create an executable
+shell script, @file{config.status}. The main purpose of this file
+is to allow the Makefile for the current directory to rebuild itself, if
+necessary. For this reason, @file{config.status} uses the
+@samp{-norecursion} option to @code{configure}, and is therefore
+probably inappropriate for reconfiguring a tree of source code.
@node Makefile Fragments, , config.status, Reference
@section Makefile Fragments
@cindex Makefile fragments
-Coming soon. FIXME-soon.
+Cygnus @code{configure} uses three types of Makefile fragments. In a
+generated Makefile they appear in the order target fragment, host
+fragment, and site fragment. This allows host fragments to override
+target fragments, and site fragments to override both.
+
+Host specific Makefile fragments conventionally reside in the
+@file{./config} directory with names of the form
+@file{mh-@var{host}}. They are used for hosts that require
+odd options to the standard compiler and for compile time options based
+on the host configuration.
+
+Target specific Makefile fragments conventionally reside in the
+@file{./config} directory with names of the form @file{mt-@var{target}}.
+They are used for target dependent compile time options.
+
+Site specific Makefile fragments conventionally reside in the
+@file{./config} directory with names of the form @file{ms-@var{site}}.
+They are used to override host and target independent compile time
+options. Note that you can also override these options on the
+@code{make} invocation line.
@node Known Bugs, Variables Index, Reference, top
@chapter Known Bugs
@cindex bugs
-The following bugs are known to exist.
+We know of the following bugs:
@itemize @bullet
projects / deliverable / binutils-gdb.git / blobdiff