@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.
@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, 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
* 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 for each source
-directory for each host and target combination.
-@*
-NOTE: support for multiple hosts and targets is at least temporarily
-suspended.
+configured. When configure runs, it does the following things.
@table @emph
@item Create build directories
directory, creating under it a directory tree that parallels the
directory structure under the source directory. (See @ref{Invoking}).
-NOTE: support for @code{-subdirs} is at least temporarily suspended.
-@*
-When you run @code{configure} with the @code{-subdirs} option, it
-creates a build subdirectory in each source directory.
-
-If you use both @code{-subdirs} and @code{-srcdir=}, a tree that
-parallels the source directory structure is created in the current
-directory, and the subdirectories are created in this directory tree
-rather than in the source directories.
-
@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{-datadir=} 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. (see @ref{Command Files, , ,
-gdb, Command Files}.)
-@c There doesn't seem to be anything else about this. Is the build-dir
-@c .gdbinit identical with the source-dir one? If so should say "copy"
-@c rather than "create" to make it clear.
+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
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.
-(see @ref{Top, , , bash}.)
-@c That's a rather extraordinary xref. What's it meant to clarify
-@c ---shell scripts in general??
@item Recursion
If the source directory has subdirectories that should also be
@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 -datadir=@var{dir}
-Configure the source to install host independent files in @var{dir}.
+@item -exec_prefix=@var{dir}
+Configure the source to install host dependent files 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 @ref{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
Configure to use the @sc{GNU} assembler.
FIXME-soon: I don't think this option should be documented.
@c Then why does it exist? /Pesch 7jan92
-@item -namesubdir=@var{name}
-NOTE: support for this @code{-namesubdir=} is at least temporarily
-suspended. FIXME-soon
-
-Name any subdirectories created by the @code{-subdirs} option
-@file{@var{name}}.
-
-@emph{Warning:} Avoid using this option if you specify multiple hosts
-simultaneously. There is no way to specify separate names for
-subdirectories, when you configure for multiple hosts in a single
-invocation of @code{configure}.
-
@item -nfp
-@c singular "target" due to apparent direction of configure.
@emph{No floating point} unit available on the target; configure to
avoid dependencies on hardware floating point.
-@c Can we even say "configure to use software floating point support"?
@item -norecursion
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}).
-@c Why *does* that use no recursion? Speed? geometric combinations
-@c under some other script?
-
-@ignore
-@c This is complicated enough without "no longer supported" entries.
-@c Should really delete this, but for ease of discourse...
-@item -objdir=@var{dir}
-This option is no longer supported. Use @code{-srcdir=} instead.
-@end ignore
@item -prefix=@var{dir}
Configure the source to install programs and files under directory
@file{@var{dir}}.
-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 @ref{Install Details}.)
+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 -recurring
-@c Wouldn't it make more sense to call this "-quiet"?
+@c Wouldn't it make more sense to call this "-quiet"? (FIXME).
This option is used internally by @code{configure} when recurring on
subdirectories. Its sole purpose is to suppress status output. You can
override this effect with the @code{-verbose} option.
Build Makefiles to use the sources located in directory @file{@var{dir}}. The
build directory is assumed to be @file{.}.
-@item -subdirs
-NOTE: support for this @code{-subdirs} is at least temporary suspended.
-FIXME-soon
-
-Place configurations in subdirectories of each build directory.
-@code{configure} builds a separate subdirectory for each host specified,
-and names it @file{H-@var{host}}. If a configuration is not native,
-(@var{host} is not @var{target}), then the subdirectory is named
-@file{X-@var{host}-@var{target}} instead. You can also name a
-subdirectory explicitly using the @samp{-namesubdir} option, but this is
-effective only when you specify one configuration at a time.
-
@item -target=@var{target}
Requests that the sources be configured to target the @var{target}
machine. If no target is specified explicitly, the target is assumed
to be the same as the host.
-NOTE: support for multiple targets is at least temporarily suspended.
-FIXME-soon
-@*
-If multiple targets are specified, configurations for each
-are created and @code{-subdirs} is assumed.
-
@item -tmpdir=@var{tmpdir}
Use the directory @var{tmpdir} for @code{configure}'s temporary files.
-@c default?
+The default is the value of the environment variable TMPDIR, or
+@file{/tmp} if the environment variable is not set.
@item -verbose
@itemx -v
@menu
* prefix:: Changing the default install directory
-* datadir:: How to separate host independent files
+* 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
@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
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=}.
-@c This is self-referential. What was intended?: (See @ref{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
-By default, host independent files are installed in subdirectories of
-@file{@var{prefix}/lib}. The location is determined by the value of the
-@code{configure} variable @code{datadir}, which determines the value of
-the Makefile variable @code{datadir}. This makes it simpler to install
+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.
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} to place host
-specific programs in subdirectories of @file{/usr/gnu/H-@var{host1}},
-and host independent files in @file{/usr/gnu/H-independent}.
-@c Self-ref? (See @ref{datadir}.)
+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 specific files.
The third line reconfigures the source for @var{host2} to place host
-specific programs in subdirectories of @file{/usr/gnu/H-@var{host2}},
-and host independent files (once again) in
-@file{/usr/gnu/H-independent}.
+specific programs in subdirectories of @file{/usr/gnu/H-@var{host2}}.
The fourth line builds and installs all programs for @var{host2}. 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.
-@c Won't make notice the installed copies aren't out of date and leave
-@c 'em alone?
-NOTE: support for @code{-subdirs} and multiple hosts is at least
-temporarily suspended. FIXME-soon
-@*
-Previously this was:
-
-@example
-configure @var{host1} @var{host2} -prefix=/usr/gnu
-@c and make something-or-other, surely?
-@end example
-
-@node Install Details, , datadir, Install Locations
+@node Install Details, , exec_prefix, Install Locations
@subsection Full descriptions of all installation subdirectories
During any install, a number of standard directories are created. Their
The default value for @code{bindir} is @file{$(prefix)/bin}.
@end defvr
-@vindex datadir
-@defvr {Makefile and configure} datadir
-A directory for host independent files. You can specify the Makefile
-default value by using the @code{-datadir=} option to @code{configure}.
-(See also @ref{Invoking}.) The default value for @code{datadir} is
-@file{$(prefix)/lib}.
+@vindex exec_prefix
+@defvr {Makefile and configure} exec_prefix
+A directory for host dependent files. You can specify the Makefile
+default value by using the @code{-exec_prefix=} option to @code{configure}.
+(See also @ref{Invoking}.) The default value for @code{exec_prefix} is
+@file{$(prefix)}.
@end defvr
@vindex libdir
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{$(datadir)/man}.
+The default value for @code{mandir} is @file{$(prefix)/man}.
@end defvr
@vindex man@var{N}dir
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{$(datadir)/info}.
+@code{infodir} is @file{$(prefix)/info}.
@end defvr
@vindex docdir
@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
@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.
-@c "Makefile" treated as ordinary word through most of this; I've left it
-@c that way since that seems to agree w ordinary usage. This one was
-@c @code'd; if the intent is to emphasize that we're now talking of it
-@c as a file, I suggest
-@c "...builds @file{Makefile} files"
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}
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.
-@quotation
-@emph{NOTE:} The rest of this section describes the @code{-subdirs} feature for
-which support is at least temporarily suspended. FIXME-soon.
-@end quotation
-
-Another way to specify the build directory is with the @samp{-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, configuring for multiple hosts or multiple targets implies
-@samp{-subdirs}.
-
-When configuring for cross tools (the converse of native tools: when the
-host is not the target), as in:
-
-@example
-configure @var{host} +target=@var{targ} -subdirs
-@end example
-
-@noindent
-the subdirectories are named @file{X-@var{host}-@var{targ}}. This is
-especially useful when configuring for multiple targets.
-
-If you use both @samp{-subdirs} and @samp{-srcdir=}, a tree that
-parallels the source directory structure is created in the current
-directory, and the subdirectories are created in this directory
-tree rather than in the source directories.
-
-@emph{NOTE:} previously, @samp{-subdirs} built two-level subdirectories
-as @file{./H-@var{host}/T-@var{target}}, created
-@file{./H-@var{host}/Makefile} for building across all targets,
-@file{./Makefile} for building across all hosts, and
-@file{./config.status} and @file{./H-@var{host}/config.status} for
-rebuilding these Makefiles.
-
@node Host, Target, Build Directories, Using Configure
@section Host
-@quotation
-@emph{NOTE:} support for multiple hosts is at least temporarily suspended.
-FIXME-soon.
-@end quotation
-
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 physical machine involved,
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 @ref{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
configuration defaults to the same as the @emph{host}.
For building cross development tools, please see @ref{Building
-Development Environments, , cfg-paper, On Configuring Development
-Tools}.
+Development Environments, , Building Development Environments,
+cfg-paper, On Configuring Development Tools}.
@node Local Conventions, , Target, Using Configure
@section Local Conventions
@code{autoconf} instead of Cygnus configure. @code{autoconf} will
be available soon from the @sc{fsf}.
-@c ..............................pesch rev..............................
-
-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 @ref{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 @ref{Hosts and
-Targets}.
+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 they can be overridden with site
-specific Makefile fragments.
+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,
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
directory with more generic names. (see also @ref{Build Directories}).
The format of configure.in is described in @ref{configure.in}.
-@item Rename the Makefile to Makefile.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 currently uses Cygnus
+To add a host or target to a program that already uses Cygnus
configure, do the following.
@itemize @bullet
configuration files. If not, add it. Also see @ref{configure.in}.
@item
-Look in @file{configure.in} for the assignments to the variables
-@code{files}, @code{links}, @code{host_makefile_frag}, and
-@code{target_makefile_frag}. These are the names of the configuration
-files that the program uses. Make sure that copies of the files exist
-for your host. If not, create them. See also @ref{Configure
-Variables}.
-
+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 now
-is the hard work of the port.
-
+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
now.
@item
-If the program does not have a @file{./config} directory, create it.
+If the program source does not have a @file{./config} directory, create it.
@item
Create a file called @file{./config/ms-@var{site}} where @var{site} is
-the name of your site. In it, set the Makefile variables of your
-choice.
+the name of your site. In it, set whatever Makefile variables you need
+to override to match your site's conventions.
@item
Configure the program with:
@end example
@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
-
-@cindex info
+@kindex info
@item info
Build all info files from texinfo source.
-@cindex install-info
+@kindex install-info
@item install-info
Install all info files.
-@cindex clean-info
+@kindex clean-info
@item clean-info
Remove all info files and any intermediate files that can be generated
from texinfo source.
-@cindex stage1
+@kindex stage1
@item stage1
-@cindex stage2
-@item stage2
-@cindex stage3
-@item stage3
-@cindex stage4
-@item stage4
-@cindex de-stage1
-@item de-stage1
-@cindex de-stage2
-@item de-stage2
-@cindex de-stage3
-@item de-stage3
-@cindex de-stage4
-@item de-stage4
-@cindex bootstrap
-@item bootstrap
-@cindex comparison
-@item comparison
-@cindex Makefile
-@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
-
-@cindex install
+@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.
-@cindex clean
+@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
-
-@cindex docdir
+@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.
-@cindex includedir
+@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
-@cindex manext
+@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? See also @ref{Install Details}.
+for @file{/usr/local/lib/man/man5/bar.5}, then what is the desired value
+of @code{manext}?
-@cindex datadir
+@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.
-
-@cindex mandir
+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}.
-@cindex infodir
+@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}.
-@cindex BISON
+@kindex BISON
@item BISON
-is assumed to have a yacc calling convention. To 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} on the installed library. 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.
-
+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.
@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 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 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}
distinguish betwen the numerous variations between @emph{common}
operating systems or object file formats. Sometimes it is used to
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
machines with @emph{no floating point} unit, even if the targets
ordinarily have floating point units available. This option has no
@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 all target machines have gas available even if they ordinarily do
-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}
on all hosts, regardless of what is normally available on them.
@end defvar
-NOTE: support for @code{-subdirs} is at least temporarily suspended.
-
@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
@end example
@node config.status, Makefile Fragments, configure.in, Reference
-@section config.status
+@section @code{config.status}
-@cindex config.status
+@kindex config.status
The final step in configuring a directory is to create an executable
-shell script call @file{config.status}. This file is typically used to
-rebuild the Makefile for the current directory. For this reason,
-@file{config.status} uses the @code{-norecursion} option to configure
-and is therefor probably inappropriate for reconfiguring a tree
-of source code.
+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
-Cygnus configure uses three types of Makefile fragments. In a
-generated Makefile they occur in the order target fragment, host
-fragment, and site fragment. This is so host fragments can override
-target fragments etc.
+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
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 these options can also be overridden on the
+options. Note that you can also override these options on the
@code{make} invocation line.
@node Known Bugs, Variables Index, Reference, top
@cindex bugs
-The following bugs are known to exist.
+We know of the following bugs:
@itemize @bullet
projects / binutils-gdb.git / blobdiff