[Top] | [Contents] | [Index] | [ ? ] |
This file documents the GNU Automake package. Automake is a program which creates GNU standards-compliant Makefiles from template files. This edition documents version 1.7.2.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake is a tool for automatically generating `Makefile.in's from
files called `Makefile.am'. Each `Makefile.am' is basically a
series of make
variable definitions(1), with
rules being thrown in occasionally. The generated `Makefile.in's
are compliant with the GNU Makefile standards.
The GNU Makefile Standards Document (see section `Makefile Conventions' in The GNU Coding Standards) is long, complicated, and subject to change. The goal of Automake is to remove the burden of Makefile maintenance from the back of the individual GNU maintainer (and put it on the back of the Automake maintainer).
The typical Automake input file is simply a series of variable definitions. Each such file is processed to create a `Makefile.in'. There should generally be one `Makefile.am' per directory of a project.
Automake does constrain a project in certain ways; for instance it assumes that the project uses Autoconf (see section `Introduction' in The Autoconf Manual), and enforces certain restrictions on the `configure.in' contents(2).
Automake requires perl
in order to generate the
`Makefile.in's. However, the distributions created by Automake are
fully GNU standards-compliant, and do not require perl
in order
to be built.
Mail suggestions and bug reports for Automake to [email protected].
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
The following sections cover a few basic ideas that will help you understand how Automake works.
2.1 General Operation General operation of Automake 2.2 Strictness Standards conformance checking 2.3 The Uniform Naming Scheme 2.4 How derived variables are named 2.5 Variables reserved for the user 2.6 Programs automake might require
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake works by reading a `Makefile.am' and generating a `Makefile.in'. Certain variables and targets defined in the `Makefile.am' instruct Automake to generate more specialized code; for instance, a `bin_PROGRAMS' variable definition will cause targets for compiling and linking programs to be generated.
The variable definitions and targets in the `Makefile.am' are copied
verbatim into the generated file. This allows you to add arbitrary code
into the generated `Makefile.in'. For instance the Automake
distribution includes a non-standard cvs-dist
target, which the
Automake maintainer uses to make distributions from his source control
system.
Note that most GNU make extensions are not recognized by Automake. Using such extensions in a `Makefile.am' will lead to errors or confusing behavior.
A special exception is that the GNU make append operator, `+=', is supported. This operator appends its right hand argument to the variable specified on the left. Automake will translate the operator into an ordinary `=' operator; `+=' will thus work with any make program.
Automake tries to keep comments grouped with any adjoining targets or variable definitions.
A target defined in `Makefile.am' generally overrides any such
target of a similar name that would be automatically generated by
automake
. Although this is a supported feature, it is generally
best to avoid making use of it, as sometimes the generated rules are
very particular.
Similarly, a variable defined in `Makefile.am' or AC_SUBST
'ed
from `configure.in' will override any definition of the variable that
automake
would ordinarily create. This feature is more often
useful than the ability to override a target definition. Be warned that
many of the variables generated by automake
are considered to be for
internal use only, and their names might change in future releases.
When examining a variable definition, Automake will recursively examine
variables referenced in the definition. For example, if Automake is
looking at the content of foo_SOURCES
in this snippet
xs = a.c b.c foo_SOURCES = c.c $(xs) |
it would use the files `a.c', `b.c', and `c.c' as the
contents of foo_SOURCES
.
Automake also allows a form of comment which is not copied into the output; all lines beginning with `##' (leading spaces allowed) are completely ignored by Automake.
It is customary to make the first line of `Makefile.am' read:
## Process this file with automake to produce Makefile.in |
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
While Automake is intended to be used by maintainers of GNU packages, it does make some effort to accommodate those who wish to use it, but do not want to use all the GNU conventions.
To this end, Automake supports three levels of strictness---the strictness indicating how stringently Automake should check standards conformance.
The valid strictness levels are:
For more information on the precise implications of the strictness
level, see 21. The effect of --gnu
and --gnits
.
Automake also has a special "cygnus" mode which is similar to
strictness but handled differently. This mode is useful for packages
which are put into a "Cygnus" style tree (e.g., the GCC tree). For
more information on this mode, see 22. The effect of --cygnus
.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake variables generally follow a uniform naming scheme that
makes it easy to decide how programs (and other derived objects) are
built, and how they are installed. This scheme also supports
configure
time determination of what should be built.
At make
time, certain variables are used to determine which
objects are to be built. The variable names are made of several pieces
which are concatenated together.
The piece which tells automake what is being built is commonly called
the primary. For instance, the primary PROGRAMS
holds a
list of programs which are to be compiled and linked.
A different set of names is used to decide where the built objects
should be installed. These names are prefixes to the primary which
indicate which standard directory should be used as the installation
directory. The standard directory names are given in the GNU standards
(see section `Directory Variables' in The GNU Coding Standards).
Automake extends this list with pkglibdir
, pkgincludedir
,
and pkgdatadir
; these are the same as the non-`pkg'
versions, but with `@PACKAGE@' appended. For instance,
pkglibdir
is defined as $(libdir)/@PACKAGE@
.
For each primary, there is one additional variable named by prepending
`EXTRA_' to the primary name. This variable is used to list
objects which may or may not be built, depending on what
configure
decides. This variable is required because Automake
must statically know the entire list of objects that may be built in
order to generate a `Makefile.in' that will work in all cases.
For instance, cpio
decides at configure time which programs are
built. Some of the programs are installed in bindir
, and some
are installed in sbindir
:
EXTRA_PROGRAMS = mt rmt bin_PROGRAMS = cpio pax sbin_PROGRAMS = @MORE_PROGRAMS@ |
Defining a primary without a prefix as a variable, e.g.,
PROGRAMS
, is an error.
Note that the common `dir' suffix is left off when constructing the variable names; thus one writes `bin_PROGRAMS' and not `bindir_PROGRAMS'.
Not every sort of object can be installed in every directory. Automake will flag those attempts it finds in error. Automake will also diagnose obvious misspellings in directory names.
Sometimes the standard directories--even as augmented by Automake---
are not enough. In particular it is sometimes useful, for clarity, to
install objects in a subdirectory of some predefined directory. To this
end, Automake allows you to extend the list of possible installation
directories. A given prefix (e.g. `zar') is valid if a variable of
the same name with `dir' appended is defined (e.g. zardir
).
For instance, until HTML support is part of Automake, you could use this to install raw HTML documentation:
htmldir = $(prefix)/html html_DATA = automake.html |
The special prefix `noinst' indicates that the objects in question should be built but not installed at all. This is usually used for objects required to build the rest of your package, for instance static libraries (see section 9.2 Building a library), or helper scripts.
The special prefix `check' indicates that the objects in question
should not be built until the make check
command is run. Those
objects are not installed either.
The current primary names are `PROGRAMS', `LIBRARIES', `LISP', `PYTHON', `JAVA', `SCRIPTS', `DATA', `HEADERS', `MANS', and `TEXINFOS'.
Some primaries also allow additional prefixes which control other
aspects of automake
's behavior. The currently defined prefixes
are `dist_', `nodist_', and `nobase_'. These prefixes
are explained later (see section 9.4 Program and Library Variables).
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Sometimes a Makefile variable name is derived from some text the maintainer supplies. For instance, a program name listed in `_PROGRAMS' is rewritten into the name of a `_SOURCES' variable. In cases like this, Automake canonicalizes the text, so that program names and the like do not have to follow Makefile variable naming rules. All characters in the name except for letters, numbers, the strudel (@), and the underscore are turned into underscores when making variable references.
For example, if your program is named sniff-glue
, the derived
variable name would be sniff_glue_SOURCES
, not
sniff-glue_SOURCES
. Similarly the sources for a library named
libmumble++.a
should be listed in the
libmumble___a_SOURCES
variable.
The strudel is an addition, to make the use of Autoconf substitutions in variable names less obfuscating.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Some Makefile
variables are reserved by the GNU Coding Standards
for the use of the "user" -- the person building the package. For
instance, CFLAGS
is one such variable.
Sometimes package developers are tempted to set user variables such as
CFLAGS
because it appears to make their job easier -- they don't
have to introduce a second variable into every target.
However, the package itself should never set a user variable, particularly not to include switches which are required for proper compilation of the package. Since these variables are documented as being for the package builder, that person rightfully expects to be able to override any of these variables at build time.
To get around this problem, automake introduces an automake-specific
shadow variable for each user flag variable. (Shadow variables are not
introduced for variables like CC
, where they would make no
sense.) The shadow variable is named by prepending `AM_' to the
user variable's name. For instance, the shadow variable for
YFLAGS
is AM_YFLAGS
.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake sometimes requires helper programs so that the generated `Makefile' can do its work properly. There are a fairly large number of them, and we list them here.
ansi2knr.c
ansi2knr.1
compile
config.guess
config.sub
depcomp
elisp-comp
install-sh
install
program which works on
platforms where install
is unavailable or unusable.
mdate-sh
missing
missing
prints an informative warning and attempts to fix things so that the
build can continue.
mkinstalldirs
mkdir -p
is not portable.
py-compile
texinfo.tex
make dvi
, make ps
and make pdf
to work when Texinfo sources are in the package.
ylwrap
lex
and yacc
and ensures that, for
instance, multiple yacc
instances can be invoked in a single
directory in parallel.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
3.1 A simple example, start to finish 3.2 A classic program 3.3 Building true and false
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Let's suppose you just finished writing zardoz
, a program to make
your head float from vortex to vortex. You've been using Autoconf to
provide a portability framework, but your `Makefile.in's have been
ad-hoc. You want to make them bulletproof, so you turn to Automake.
The first step is to update your `configure.in' to include the
commands that automake
needs. The way to do this is to add an
AM_INIT_AUTOMAKE
call just after AC_INIT
:
AC_INIT(zardoz, 1.0) AM_INIT_AUTOMAKE ... |
Since your program doesn't have any complicating factors (e.g., it
doesn't use gettext
, it doesn't want to build a shared library),
you're done with this part. That was easy!
Now you must regenerate `configure'. But to do that, you'll need
to tell autoconf
how to find the new macro you've used. The
easiest way to do this is to use the aclocal
program to generate
your `aclocal.m4' for you. But wait... maybe you already have an
`aclocal.m4', because you had to write some hairy macros for your
program. The aclocal
program lets you put your own macros into
`acinclude.m4', so simply rename and then run:
mv aclocal.m4 acinclude.m4 aclocal autoconf |
Now it is time to write your `Makefile.am' for zardoz
.
Since zardoz
is a user program, you want to install it where the
rest of the user programs go: bindir
. Additionally,
zardoz
has some Texinfo documentation. Your `configure.in'
script uses AC_REPLACE_FUNCS
, so you need to link against
`@LIBOBJS@'. So here's what you'd write:
bin_PROGRAMS = zardoz zardoz_SOURCES = main.c head.c float.c vortex9.c gun.c zardoz_LDADD = @LIBOBJS@ info_TEXINFOS = zardoz.texi |
Now you can run automake --add-missing
to generate your
`Makefile.in' and grab any auxiliary files you might need, and
you're done!
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
GNU hello is renowned for its classic simplicity and versatility. This section shows how Automake could be used with the GNU Hello package. The examples below are from the latest beta version of GNU Hello, but with all of the maintainer-only code stripped out, as well as all copyright comments.
Of course, GNU Hello is somewhat more featureful than your traditional two-liner. GNU Hello is internationalized, does option processing, and has a manual and a test suite.
Here is the `configure.in' from GNU Hello:
dnl Process this file with autoconf to produce a configure script. AC_INIT(src/hello.c) AM_INIT_AUTOMAKE(hello, 1.3.11) AM_CONFIG_HEADER(config.h) dnl Set of available languages. ALL_LINGUAS="de fr es ko nl no pl pt sl sv" dnl Checks for programs. AC_PROG_CC AC_ISC_POSIX dnl Checks for libraries. dnl Checks for header files. AC_STDC_HEADERS AC_HAVE_HEADERS(string.h fcntl.h sys/file.h sys/param.h) dnl Checks for library functions. AC_FUNC_ALLOCA dnl Check for st_blksize in struct stat AC_ST_BLKSIZE dnl internationalization macros AM_GNU_GETTEXT AC_OUTPUT([Makefile doc/Makefile intl/Makefile po/Makefile.in \ src/Makefile tests/Makefile tests/hello], [chmod +x tests/hello]) |
The `AM_' macros are provided by Automake (or the Gettext library); the rest are standard Autoconf macros.
The top-level `Makefile.am':
EXTRA_DIST = BUGS ChangeLog.O SUBDIRS = doc intl po src tests |
As you can see, all the work here is really done in subdirectories.
The `po' and `intl' directories are automatically generated
using gettextize
; they will not be discussed here.
In `doc/Makefile.am' we see:
info_TEXINFOS = hello.texi hello_TEXINFOS = gpl.texi |
This is sufficient to build, install, and distribute the GNU Hello manual.
Here is `tests/Makefile.am':
TESTS = hello EXTRA_DIST = hello.in testdata |
The script `hello' is generated by configure
, and is the
only test case. make check
will run this test.
Last we have `src/Makefile.am', where all the real work is done:
bin_PROGRAMS = hello hello_SOURCES = hello.c version.c getopt.c getopt1.c getopt.h system.h hello_LDADD = @INTLLIBS@ @ALLOCA@ localedir = $(datadir)/locale INCLUDES = -I../intl -DLOCALEDIR=\"$(localedir)\" |
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Here is another, trickier example. It shows how to generate two
programs (true
and false
) from the same source file
(`true.c'). The difficult part is that each compilation of
`true.c' requires different cpp
flags.
bin_PROGRAMS = true false false_SOURCES = false_LDADD = false.o true.o: true.c $(COMPILE) -DEXIT_CODE=0 -c true.c false.o: true.c $(COMPILE) -DEXIT_CODE=1 -o false.o -c true.c |
Note that there is no true_SOURCES
definition. Automake will
implicitly assume that there is a source file named `true.c', and
define rules to compile `true.o' and link `true'. The
true.o: true.c
rule supplied by the above `Makefile.am',
will override the Automake generated rule to build `true.o'.
false_SOURCES
is defined to be empty--that way no implicit value
is substituted. Because we have not listed the source of
`false', we have to tell Automake how to link the program. This is
the purpose of the false_LDADD
line. A false_DEPENDENCIES
variable, holding the dependencies of the `false' target will be
automatically generated by Automake from the content of
false_LDADD
.
The above rules won't work if your compiler doesn't accept both
`-c' and `-o'. The simplest fix for this is to introduce a
bogus dependency (to avoid problems with a parallel make
):
true.o: true.c false.o $(COMPILE) -DEXIT_CODE=0 -c true.c false.o: true.c $(COMPILE) -DEXIT_CODE=1 -c true.c && mv true.o false.o |
Also, these explicit rules do not work if the de-ANSI-fication feature is used (see section 9.13 Automatic de-ANSI-fication). Supporting de-ANSI-fication requires a little more work:
true._o: true._c false.o $(COMPILE) -DEXIT_CODE=0 -c true.c false._o: true._c $(COMPILE) -DEXIT_CODE=1 -c true.c && mv true._o false.o |
As it turns out, there is also a much easier way to do this same task.
Some of the above techniques are useful enough that we've kept the
example in the manual. However if you were to build true
and
false
in real life, you would probably use per-program
compilation flags, like so:
bin_PROGRAMS = false true false_SOURCES = true.c false_CPPFLAGS = -DEXIT_CODE=1 true_SOURCES = true.c true_CPPFLAGS = -DEXIT_CODE=0 |
In this case Automake will cause `true.c' to be compiled twice, with different flags. De-ANSI-fication will work automatically. In this instance, the names of the object files would be chosen by automake; they would be `false-true.o' and `true-true.o'. (The name of the object files rarely matters.)
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
To create all the `Makefile.in's for a package, run the
automake
program in the top level directory, with no arguments.
automake
will automatically find each appropriate
`Makefile.am' (by scanning `configure.in'; see section 5. Scanning `configure.in')
and generate the corresponding `Makefile.in'. Note that
automake
has a rather simplistic view of what constitutes a
package; it assumes that a package has only one `configure.in', at
the top. If your package has multiple `configure.in's, then you
must run automake
in each directory holding a
`configure.in'. (Alternatively, you may rely on Autoconf's
autoreconf
, which is able to recurse your package tree and run
automake
where appropriate.)
You can optionally give automake
an argument; `.am' is
appended to the argument and the result is used as the name of the input
file. This feature is generally only used to automatically rebuild an
out-of-date `Makefile.in'. Note that automake
must always
be run from the topmost directory of a project, even if being used to
regenerate the `Makefile.in' in some subdirectory. This is
necessary because automake
must scan `configure.in', and
because automake
uses the knowledge that a `Makefile.in' is
in a subdirectory to change its behavior in some cases.
Automake will run autoconf
to scan `configure.in' and its
dependencies (`aclocal.m4'), therefore autoconf
must be in
your PATH
. If there is an AUTOCONF
variable in your
environment it will be used instead of autoconf
, this allows you
to select a particular version of Autoconf. By the way, don't
misunderstand this paragraph: Automake runs autoconf
to
scan your `configure.in', this won't build
`configure' and you still have to run autoconf
yourself for
this purpose.
automake
accepts the following options:
AC_CANONICAL_HOST
. Automake is distributed with several of these
files (see section 2.6 Programs automake might require); this option will cause the missing
ones to be automatically added to the package, whenever possible. In
general if Automake tells you a file is missing, try using this option.
By default Automake tries to make a symbolic link pointing to its own
copy of the missing file; this can be changed with --copy
.
--add-missing
, causes installed files to be
copied. The default is to make a symbolic link.
--cygnus
.
--add-missing
, causes standard files to be reinstalled
even if they already exist in the source tree. This involves removing
the file from the source tree before creating the new symlink (or, with
--copy
, copying the new file).
--gnu
and --gnits
.
--gnu
and --gnits
. This is the default strictness.
automake
creates all `Makefile.in's mentioned in
`configure.in'. This option causes it to only update those
`Makefile.in's which are out of date with respect to one of their
dependents.
A category can be turned off by prefixing its name with `no-'. For instance `-Wno-syntax' will hide the warnings about unused variables.
The categories output by default are `syntax' and `unsupported'. Additionally, `gnu' is enabled in `--gnu' and `--gnits' strictness.
`portability' warnings are currently disabled by default, but they will be enabled in `--gnu' and `--gnits' strictness in a future release.
The environment variable `WARNINGS' can contain a comma separated
list of categories to enable. It will be taken into account before the
command-line switches, this way `-Wnone' will also ignore any
warning category enabled by `WARNINGS'. This variable is also used
by other tools like autoconf
; unknown categories are ignored
for this reason.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake scans the package's `configure.in' to determine certain
information about the package. Some autoconf
macros are required
and some variables must be defined in `configure.in'. Automake
will also use information from `configure.in' to further tailor its
output.
Automake also supplies some Autoconf macros to make the maintenance
easier. These macros can automatically be put into your
`aclocal.m4' using the aclocal
program.
5.1 Configuration requirements 5.2 Other things Automake recognizes 5.3 Auto-generating aclocal.m4 5.4 aclocal options aclocal command line arguments 5.5 Macro search path Modifying aclocal's search path 5.6 Autoconf macros supplied with Automake 5.7 Writing your own aclocal macros
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
The one real requirement of Automake is that your `configure.in'
call AM_INIT_AUTOMAKE
. This macro does several things which are
required for proper Automake operation (see section 5.6 Autoconf macros supplied with Automake).
Here are the other macros which Automake requires but which are not run
by AM_INIT_AUTOMAKE
:
AC_CONFIG_FILES
AC_OUTPUT
AC_CONFIG_FILES([foo/Makefile])
will cause Automake to
generate `foo/Makefile.in' if `foo/Makefile.am' exists.
Other listed files are treated differently. Currently the only
difference is that an Automake `Makefile' is removed by make
distclean
, while other files are removed by make clean
.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Every time Automake is run it calls Autoconf to trace `configure.in'. This way it can recognize the use of certain macros and tailor the generated `Makefile.in' appropriately. Currently recognized macros and their effects are:
AC_CONFIG_HEADERS
AM_CONFIG_HEADER
(see section 5.6 Autoconf macros supplied with Automake); this is no longer the case today.
AC_CONFIG_AUX_DIR
AC_CANONICAL_HOST
AC_CANONICAL_SYSTEM
AC_CANONICAL_HOST
, but also defines the
`Makefile' variables `build_alias' and `target_alias'.
See section `Getting the Canonical System Type' in The Autoconf Manual.
AC_LIBSOURCE
AC_LIBSOURCES
AC_LIBOBJ
AC_LIBSOURCE
or AC_LIBSOURCES
.
Note that the AC_LIBOBJ
macro calls AC_LIBSOURCE
. So if
an Autoconf macro is documented to call AC_LIBOBJ([file])
, then
`file.c' will be distributed automatically by Automake. This
encompasses many macros like AC_FUNC_ALLOCA
,
AC_FUNC_MEMCMP
, AC_REPLACE_FUNCS
, and others.
By the way, direct assignments to LIBOBJS
are no longer
supported. You should always use AC_LIBOBJ
for this purpose.
See section `AC_LIBOBJ
vs. LIBOBJS
' in The Autoconf Manual.
AC_PROG_RANLIB
AC_PROG_CXX
AC_PROG_F77
AC_F77_LIBRARY_LDFLAGS
AC_PROG_LIBTOOL
libtool
(see section `Introduction' in The Libtool Manual).
AC_PROG_YACC
AC_PROG_LEX
AC_SUBST
If the Autoconf manual says that a macro calls AC_SUBST
for
var, or defined the output variable var then var will
be defined in each generated `Makefile.in'.
E.g. AC_PATH_XTRA
defines X_CFLAGS
and X_LIBS
, so
you can use the variable in any `Makefile.am' if
AC_PATH_XTRA
is called.
AM_C_PROTOTYPES
AM_GNU_GETTEXT
AM_MAINTAINER_MODE
configure
. If this is used, automake
will cause
`maintainer-only' rules to be turned off by default in the
generated `Makefile.in's. This macro defines the
`MAINTAINER_MODE' conditional, which you can use in your own
`Makefile.am'.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake includes a number of Autoconf macros which can be used in your
package; some of them are actually required by Automake in certain
situations. These macros must be defined in your `aclocal.m4';
otherwise they will not be seen by autoconf
.
The aclocal
program will automatically generate `aclocal.m4'
files based on the contents of `configure.in'. This provides a
convenient way to get Automake-provided macros, without having to
search around. Also, the aclocal
mechanism allows other packages
to supply their own macros.
At startup, aclocal
scans all the `.m4' files it can find,
looking for macro definitions (see section 5.5 Macro search path). Then it
scans `configure.in'. Any
mention of one of the macros found in the first step causes that macro,
and any macros it in turn requires, to be put into `aclocal.m4'.
The contents of `acinclude.m4', if it exists, are also automatically included in `aclocal.m4'. This is useful for incorporating local macros into `configure'.
aclocal
tries to be smart about looking for new AC_DEFUN
s
in the files it scans. It also
tries to copy the full text of the scanned file into `aclocal.m4',
including both `#' and `dnl' comments. If you want to make a
comment which will be completely ignored by aclocal
, use
`##' as the comment leader.
5.4 aclocal options Options supported by aclocal 5.5 Macro search path How aclocal finds .m4 files
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
aclocal
accepts the following options:
--acdir=dir
--help
-I dir
--output=file
--print-ac-dir
aclocal
will search to
find third-party `.m4' files. When this option is given, normal
processing is suppressed. This option can be used by a package to
determine where to install a macro file.
--verbose
--version
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
By default, aclocal
searches for `.m4' files in the following
directories, in this order:
acdir-APIVERSION
1.6
.
acdir
automake
itself is built. This is
`@datadir@/aclocal/', which typically
expands to `${prefix}/share/aclocal/'. To find the compiled-in
value of acdir, use the --print-ac-dir
option
(see section 5.4 aclocal options).
As an example, suppose that automake-1.6.2 was configured with
--prefix=/usr/local
. Then, the search path would be:
As explained in (see section 5.4 aclocal options), there are several options that can be used to change or extend this search path.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
--acdir
The most obvious option to modify the search path is
--acdir=dir
, which changes default directory and
drops the APIVERSION directory. For example, if one specifies
--acdir=/opt/private/
, then the search path becomes:
Note that this option, --acdir
, is intended for use
by the internal automake test suite only; it is not ordinarily
needed by end-users.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
-I dir
Any extra directories specified using -I
options
(see section 5.4 aclocal options) are prepended to this search list. Thus,
aclocal -I /foo -I /bar
results in the following search path:
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
There is a third mechanism for customizing the search path. If a `dirlist' file exists in acdir, then that file is assumed to contain a list of directories, one per line, to be added to the search list. These directories are searched after all other directories.
For example, suppose `acdir/dirlist' contains the following:
/test1 /test2 |
and that aclocal
was called with the -I /foo -I /bar
options.
Then, the search path would be
If the --acdir=dir
option is used, then aclocal
will search for the `dirlist' file in dir. In the
--acdir=/opt/private/
example above, aclocal
would look
for `/opt/private/dirlist'. Again, however, the --acdir
option is intended for use by the internal automake test suite only;
--acdir
is not ordinarily needed by end-users.
`dirlist' is useful in the following situation: suppose that
automake
version 1.6.2
is installed with
$prefix=/usr by the system vendor. Thus, the default search
directories are
However, suppose further that many packages have been manually
installed on the system, with $prefix=/usr/local, as is typical.
In that case, many of these "extra" `.m4' files are in
`/usr/local/share/aclocal'. The only way to force
`/usr/bin/aclocal' to find these "extra" `.m4' files
is to always call aclocal -I /usr/local/share/aclocal
.
This is inconvenient. With `dirlist', one may create the file
`/usr/share/aclocal/dirlist'
which contains only the single line
`/usr/local/share/aclocal'
Now, the "default" search path on the affected system is
without the need for -I
options; -I
options can be reserved
for project-specific needs (`my-source-dir/m4/'), rather than
using it to work around local system-dependent tool installation
directories.
Similarly, `dirlist' can be handy if you have installed a local
copy Automake on your account and want aclocal
to look for
macros installed at other places on the system.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake ships with several Autoconf macros that you can use from your
`configure.in'. When you use one of them it will be included by
aclocal
in `aclocal.m4'.
5.6.1 Public macros Macros that you can use. 5.6.2 Private macros Macros that you should not use.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
AM_CONFIG_HEADER
AC_CONFIG_HEADERS
today (see section 5.2 Other things Automake recognizes).
AM_ENABLE_MULTILIB
AM_C_PROTOTYPES
AM_HEADER_TIOCGWINSZ_NEEDS_SYS_IOCTL
TIOCGWINSZ
requires `<sys/ioctl.h>', then
define GWINSZ_IN_SYS_IOCTL
. Otherwise TIOCGWINSZ
can be
found in `<termios.h>'.
AM_INIT_AUTOMAKE([OPTIONS])
AM_INIT_AUTOMAKE(PACKAGE, VERSION, [NO-DEFINE])
This macro has two forms, the second of which has two required
arguments: the package and the version number. This latter form is
obsolete because the package and version can be obtained
from Autoconf's AC_INIT
macro (which itself has an old and a new
form).
If your `configure.in' has:
AC_INIT(src/foo.c) AM_INIT_AUTOMAKE(mumble, 1.5) |
AC_INIT(mumble, 1.5) AC_CONFIG_SRCDIR(src/foo.c) AM_INIT_AUTOMAKE |
Note that if you're upgrading your `configure.in' from an earlier
version of Automake, it is not always correct to simply move the package
and version arguments from AM_INIT_AUTOMAKE
directly to
AC_INIT
, as in the example above. The first argument of
AC_INIT
is the name of your package (e.g. `GNU Automake'),
not the tarball name (e.g. `automake') you used to pass to
AM_INIT_AUTOMAKE
. Autoconf's rule to derive a tarball name from
the package name should work for most but not all packages. Especially,
if your tarball name is not all lower case, you will have to use the
four-argument form of AC_INIT
(supported in Autoconf versions
greater than 2.52g).
When AM_INIT_AUTOMAKE
is called with a single argument, it is
interpreted as a space-separated list of Automake options which should
be applied to every `Makefile.am' in the tree. The effect is as if
each option were listed in AUTOMAKE_OPTIONS
.
By default this macro AC_DEFINE
's `PACKAGE' and
`VERSION'. This can be avoided by passing the `no-define'
option, as in:
AM_INIT_AUTOMAKE([gnits 1.5 no-define dist-bzip2]) |
AM_PATH_LISPDIR
emacs
, and, if found, sets the output
variable lispdir
to the full path to Emacs' site-lisp directory.
Note that this test assumes the emacs
found to be a version that
supports Emacs Lisp (such as GNU Emacs or XEmacs). Other emacsen
can cause this test to hang (some, like old versions of MicroEmacs,
start up in interactive mode, requiring `C-x C-c' to exit, which
is hardly obvious for a non-emacs user). In most cases, however, you
should be able to use `C-c' to kill the test. In order to avoid
problems, you can set EMACS
to "no" in the environment, or
use the `--with-lispdir' option to configure
to
explictly set the correct path (if you're sure you have an emacs
that supports Emacs Lisp.
AM_PROG_AS
CCAS
, and will also set CCASFLAGS
if required.
AM_PROG_CC_C_O
AC_PROG_CC_C_O
, but it generates its results in the
manner required by automake. You must use this instead of
AC_PROG_CC_C_O
when you need this functionality.
AM_PROG_CC_STDC
CC
to make it so. This macro tries various
options that select ANSI C on some system or another. It considers the
compiler to be in ANSI C mode if it handles function prototypes correctly.
If you use this macro, you should check after calling it whether the C
compiler has been set to accept ANSI C; if not, the shell variable
am_cv_prog_cc_stdc
is set to `no'. If you wrote your source
code in ANSI C, you can make an un-ANSIfied copy of it by using the
ansi2knr
option (see section 9.13 Automatic de-ANSI-fication).
This macro is a relic from the time Autoconf didn't offer such a
feature. AM_PROG_CC_STDC
's logic has now been merged into
Autoconf's AC_PROG_CC
macro, therefore you should use the latter
instead. Chances are you are already using AC_PROG_CC
, so you
can simply remove the AM_PROG_CC_STDC
call and turn all
occurrences of $am_cv_prog_cc_stdc
into
$ac_cv_prog_cc_stdc
. AM_PROG_CC_STDC
will be marked as
obsolete (in the Autoconf sense) in Automake 1.8.
AM_PROG_LEX
AC_PROG_LEX
(see section `Particular Program Checks' in The Autoconf Manual), but uses the
missing
script on systems that do not have lex
.
`HP-UX 10' is one such system.
AM_PROG_GCJ
gcj
program or causes an error. It sets
`GCJ' and `GCJFLAGS'. gcj
is the Java front-end to the
GNU Compiler Collection.
AM_SYS_POSIX_TERMIOS
am_cv_sys_posix_termios
to
`yes'. If not, set the variable to `no'.
AM_WITH_DMALLOC
WITH_DMALLOC
and add `-ldmalloc' to LIBS
.
AM_WITH_REGEX
configure
command line. If
specified (the default), then the `regex' regular expression
library is used, `regex.o' is put into `LIBOBJS', and
`WITH_REGEX' is defined. If `--without-regex' is given, then
the `rx' regular expression library is used, and `rx.o' is put
into `LIBOBJS'.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
The following macros are private macros you should not call directly. They are called by the other public macros when appropriate. Do not rely on them, as they might be changed in a future version. Consider them as implementation details; or better, do not consider them at all: skip this section!
_AM_DEPENDENCIES
AM_SET_DEPDIR
AM_DEP_TRACK
AM_OUTPUT_DEPENDENCY_COMMANDS
AM_MAKE_INCLUDE
make
handles
include
statements. This macro is automatically invoked when
needed; there should be no need to invoke it manually.
AM_PROG_INSTALL_STRIP
install
which can be used to
strip
a program at installation time. This macro is
automatically included when required.
AM_SANITY_CHECK
AM_INIT_AUTOMAKE
.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
The aclocal
program doesn't have any built-in knowledge of any
macros, so it is easy to extend it with your own macros.
This is mostly used for libraries which want to supply their own
Autoconf macros for use by other programs. For instance the
gettext
library supplies a macro AM_GNU_GETTEXT
which
should be used by any package using gettext
. When the library is
installed, it installs this macro so that aclocal
will find it.
A file of macros should be a series of AC_DEFUN
's. The
aclocal
programs also understands AC_REQUIRE
, so it is
safe to put each macro in a separate file. See section `Prerequisite Macros' in The Autoconf Manual, and section `Macro Definitions' in The Autoconf Manual.
A macro file's name should end in `.m4'. Such files should be
installed in `aclocal --print-ac-dir`
(which usually happens to
be `$(datadir)/aclocal').
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
In packages with subdirectories, the top level `Makefile.am' must
tell Automake which subdirectories are to be built. This is done via
the SUBDIRS
variable.
The SUBDIRS
variable holds a list of subdirectories in which
building of various sorts can occur. Many targets (e.g. all
) in
the generated `Makefile' will run both locally and in all specified
subdirectories. Note that the directories listed in SUBDIRS
are
not required to contain `Makefile.am's; only `Makefile's
(after configuration). This allows inclusion of libraries from packages
which do not use Automake (such as gettext
).
In packages that use subdirectories, the top-level `Makefile.am' is often very short. For instance, here is the `Makefile.am' from the GNU Hello distribution:
EXTRA_DIST = BUGS ChangeLog.O README-alpha SUBDIRS = doc intl po src tests |
When Automake invokes make
in a subdirectory, it uses the value
of the MAKE
variable. It passes the value of the variable
AM_MAKEFLAGS
to the make
invocation; this can be set in
`Makefile.am' if there are flags you must always pass to
make
.
The directories mentioned in SUBDIRS
must be direct children of
the current directory. For instance, you cannot put `src/subdir'
into SUBDIRS
. Instead you should put SUBDIRS = subdir
into `src/Makefile.am'. Automake can be used to construct packages
of arbitrary depth this way.
By default, Automake generates `Makefiles' which work depth-first
(`postfix'). However, it is possible to change this ordering. You
can do this by putting `.' into SUBDIRS
. For instance,
putting `.' first will cause a `prefix' ordering of
directories. All `clean' targets are run in reverse order of build
targets.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
It is possible to define the SUBDIRS
variable conditionally if,
like in the case of GNU Inetutils
, you want to only build a
subset of the entire package.
To illustrate how this works, let's assume we have two directories
`src/' and `opt/'. `src/' should always be built, but we
want to decide in ./configure
whether `opt/' will be built
or not. (For this example we will assume that `opt/' should be
built when the variable $want_opt
was set to yes
.)
Running make
should thus recurse into `src/' always, and
then maybe in `opt/'.
However make dist
should always recurse into both `src/' and
`opt/'. Because `opt/' should be distributed even if it is
not needed in the current configuration. This means `opt/Makefile'
should be created unconditionally. (3)
There are two ways to setup a project like this. You can use Automake
conditionals (see section 20. Conditionals) or use Autoconf AC_SUBST
variables (see section `Setting Output Variables' in The Autoconf Manual). Using Automake conditionals is the
preferred solution.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
AM_CONDITIONAL
`configure' should output the `Makefile' for each directory and define a condition into which `opt/' should be built.
... AM_CONDITIONAL([COND_OPT], [test "$want_opt" = yes]) AC_CONFIG_FILES([Makefile src/Makefile opt/Makefile]) ... |
Then SUBDIRS
can be defined in the top-level `Makefile.am'
as follows.
if COND_OPT MAYBE_OPT = opt endif SUBDIRS = src $(MAYBE_OPT) |
As you can see, running make
will rightly recurse into
`src/' and maybe `opt/'.
As you can't see, running make dist
will recurse into both
`src/' and `opt/' directories because make dist
, unlike
make all
, doesn't use the SUBDIRS
variable. It uses the
DIST_SUBDIRS
variable.
In this case Automake will define DIST_SUBDIRS = src opt
automatically because it knows that MAYBE_OPT
can contain
opt
in some condition.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
AC_SUBST
Another idea is to define MAYBE_OPT
from `./configure' using
AC_SUBST
:
... if test "$want_opt" = yes; then MAYBE_OPT=opt else MAYBE_OPT= fi AC_SUBST([MAYBE_OPT]) AC_CONFIG_FILES([Makefile src/Makefile opt/Makefile]) ... |
In this case the top-level `Makefile.am' should look as follows.
SUBDIRS = src $(MAYBE_OPT) DIST_SUBDIRS = src opt |
The drawback is that since Automake cannot guess what the possible
values of MAYBE_OPT
are, it is necessary to define
DIST_SUBDIRS
.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
DIST_SUBDIRS
is used
As shown in the above examples, DIST_SUBDIRS
is used by targets
that need to recurse in all directories, even those which have been
conditionally left out of the build.
Precisely, DIST_SUBDIRS
is used by make dist
, make
distclean
, and make maintainer-clean
. All other recursive
targets use SUBDIRS
.
Automake will define DIST_SUBDIRS
automatically from the
possibles values of SUBDIRS
in all conditions.
If SUBDIRS
contains AC_SUBST
variables,
DIST_SUBDIRS
will not be defined correctly because Automake
doesn't know the possible values of these variables. In this case
DIST_SUBDIRS
needs to be defined manually.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
If you've ever read Peter Miller's excellent paper,
Recursive Make Considered Harmful, the preceding section on the use of
subdirectories will probably come as unwelcome advice. For those who
haven't read the paper, Miller's main thesis is that recursive
make
invocations are both slow and error-prone.
Automake provides sufficient cross-directory support (4) to enable you to write a single `Makefile.am' for a complex multi-directory package.
By default an installable file specified in a subdirectory will have its directory name stripped before installation. For instance, in this example, the header file will be installed as `$(includedir)/stdio.h':
include_HEADERS = inc/stdio.h |
However, the `nobase_' prefix can be used to circumvent this path stripping. In this example, the header file will be installed as `$(includedir)/sys/types.h':
nobase_include_HEADERS = sys/types.h |
`nobase_' should be specified first when used in conjunction with either `dist_' or `nodist_' (see section 15. What Goes in a Distribution). For instance:
nobase_dist_pkgdata_DATA = images/vortex.pgm |
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake generates rules to automatically rebuild `Makefile's, `configure', and other derived files like `Makefile.in'.
If you are using AM_MAINTAINER_MODE
in `configure.in', then
these automatic rebuilding rules are only enabled in maintainer mode.
Sometimes you need to run aclocal
with an argument like -I
to tell it where to find `.m4' files. Since sometimes make
will automatically run aclocal
, you need a way to specify these
arguments. You can do this by defining ACLOCAL_AMFLAGS
; this
holds arguments which are passed verbatim to aclocal
. This variable
is only useful in the top-level `Makefile.am'.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
A large part of Automake's functionality is dedicated to making it easy to build programs and libraries.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
In order to build a program, you need to tell Automake which sources are part of it, and which libraries it should be linked with.
This section also covers conditional compilation of sources or programs. Most of the comments about these also apply to libraries (see section 9.2 Building a library) and Libtool libraries (see section 9.3 Building a Shared Library).
9.1.1 Defining program sources 9.1.2 Linking the program Linking with libraries or extra objects 9.1.3 Conditional compilation of sources Handling conditional sources 9.1.4 Conditional compilation of programs Building program conditionally
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
In a directory containing source that gets built into a program (as
opposed to a library or a script), the `PROGRAMS' primary is used.
Programs can be installed in bindir
, sbindir
,
libexecdir
, pkglibdir
, or not at all (`noinst').
They can also be built only for make check
, in which case the
prefix is `check'.
For instance:
bin_PROGRAMS = hello |
In this simple case, the resulting `Makefile.in' will contain code
to generate a program named hello
.
Associated with each program are several assisting variables which are named after the program. These variables are all optional, and have reasonable defaults. Each variable, its use, and default is spelled out below; we use the "hello" example throughout.
The variable hello_SOURCES
is used to specify which source files
get built into an executable:
hello_SOURCES = hello.c version.c getopt.c getopt1.c getopt.h system.h |
This causes each mentioned `.c' file to be compiled into the corresponding `.o'. Then all are linked to produce `hello'.
If `hello_SOURCES' is not specified, then it defaults to the single file `hello.c'; that is, the default is to compile a single C file whose base name is the name of the program itself. (This is a terrible default but we are stuck with it for historical reasons.)
Multiple programs can be built in a single directory. Multiple programs can share a single source file, which must be listed in each `_SOURCES' definition.
Header files listed in a `_SOURCES' definition will be included in the distribution but otherwise ignored. In case it isn't obvious, you should not include the header file generated by `configure' in a `_SOURCES' variable; this file should not be distributed. Lex (`.l') and Yacc (`.y') files can also be listed; see 9.7 Yacc and Lex support.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
If you need to link against libraries that are not found by
configure
, you can use LDADD
to do so. This variable is
used to specify additional objects or libraries to link with; it is
inappropriate for specifying specific linker flags, you should use
AM_LDFLAGS
for this purpose.
Sometimes, multiple programs are built in one directory but do not share
the same link-time requirements. In this case, you can use the
`prog_LDADD' variable (where prog is the name of the
program as it appears in some `_PROGRAMS' variable, and usually
written in lowercase) to override the global LDADD
. If this
variable exists for a given program, then that program is not linked
using LDADD
.
For instance, in GNU cpio, pax
, cpio
and mt
are
linked against the library `libcpio.a'. However, rmt
is
built in the same directory, and has no such link requirement. Also,
mt
and rmt
are only built on certain architectures. Here
is what cpio's `src/Makefile.am' looks like (abridged):
bin_PROGRAMS = cpio pax @MT@ libexec_PROGRAMS = @RMT@ EXTRA_PROGRAMS = mt rmt LDADD = ../lib/libcpio.a @INTLLIBS@ rmt_LDADD = cpio_SOURCES = ... pax_SOURCES = ... mt_SOURCES = ... rmt_SOURCES = ... |
`prog_LDADD' is inappropriate for passing program-specific linker flags (except for `-l', `-L', `-dlopen' and `-dlpreopen'). So, use the `prog_LDFLAGS' variable for this purpose.
It is also occasionally useful to have a program depend on some other target which is not actually part of that program. This can be done using the `prog_DEPENDENCIES' variable. Each program depends on the contents of such a variable, but no further interpretation is done.
If `prog_DEPENDENCIES' is not supplied, it is computed by Automake. The automatically-assigned value is the contents of `prog_LDADD', with most configure substitutions, `-l', `-L', `-dlopen' and `-dlpreopen' options removed. The configure substitutions that are left in are only `@LIBOBJS@' and `@ALLOCA@'; these are left because it is known that they will not cause an invalid value for `prog_DEPENDENCIES' to be generated.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
You can't put a configure substitution (e.g., `@FOO@') into a `_SOURCES' variable. The reason for this is a bit hard to explain, but suffice to say that it simply won't work. Automake will give an error if you try to do this.
Fortunately there are two other ways to achieve the same result. One is
to use configure substitutions in _LDADD
variables, the other is
to use an Automake conditional.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
_LDADD
substitutions
Automake must know all the source files that could possibly go into a
program, even if not all the files are built in every circumstance. Any
files which are only conditionally built should be listed in the
appropriate `EXTRA_' variable. For instance, if
`hello-linux.c' or `hello-generic.c' were conditionally included
in hello
, the `Makefile.am' would contain:
bin_PROGRAMS = hello hello_SOURCES = hello-common.c EXTRA_hello_SOURCES = hello-linux.c hello-generic.c hello_LDADD = @HELLO_SYSTEM@ hello_DEPENDENCIES = @HELLO_SYSTEM@ |
You can then setup the @HELLO_SYSTEM@
substitution from
`configure.in':
... case $host in *linux*) HELLO_SYSTEM='hello-linux.$(OBJEXT)' ;; *) HELLO_SYSTEM='hello-generic.$(OBJEXT)' ;; esac AC_SUBST([HELLO_SYSTEM]) ... |
In this case, HELLO_SYSTEM
should be replaced by
`hello-linux.o' or `hello-bsd.o', and added to
hello_DEPENDENCIES
and hello_LDADD
in order to be built
and linked in.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
An often simpler way to compile source files conditionally is to use Automake conditionals. For instance, you could use this `Makefile.am' construct to build the same `hello' example:
bin_PROGRAMS = hello if LINUX hello_SOURCES = hello-linux.c hello-common.c else hello_SOURCES = hello-generic.c hello-common.c endif |
In this case, your `configure.in' should setup the LINUX
conditional using AM_CONDITIONAL
(see section 20. Conditionals).
When using conditionals like this you don't need to use the `EXTRA_' variable, because Automake will examine the contents of each variable to construct the complete list of source files.
If your program uses a lot of files, you will probably prefer a
conditional +=
.
bin_PROGRAMS = hello hello_SOURCES = hello-common.c if LINUX hello_SOURCES += hello-linux.c else hello_SOURCES += hello-generic.c endif |
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Sometimes it is useful to determine the programs that are to be built at
configure time. For instance, GNU cpio
only builds mt
and
rmt
under special circumstances.
In this case, you must notify Automake of all the programs that can
possibly be built, but at the same time cause the generated
`Makefile.in' to use the programs specified by configure
.
This is done by having configure
substitute values into each
`_PROGRAMS' definition, while listing all optionally built programs
in EXTRA_PROGRAMS
.
Of course you can use Automake conditionals to determine the programs to be built.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Building a library is much like building a program. In this case, the
name of the primary is `LIBRARIES'. Libraries can be installed in
libdir
or pkglibdir
.
See section 9.3 Building a Shared Library, for information on how to build shared libraries using Libtool and the `LTLIBRARIES' primary.
Each `_LIBRARIES' variable is a list of the libraries to be built. For instance to create a library named `libcpio.a', but not install it, you would write:
noinst_LIBRARIES = libcpio.a |
The sources that go into a library are determined exactly as they are for programs, via the `_SOURCES' variables. Note that the library name is canonicalized (see section 2.4 How derived variables are named), so the `_SOURCES' variable corresponding to `liblob.a' is `liblob_a_SOURCES', not `liblob.a_SOURCES'.
Extra objects can be added to a library using the
`library_LIBADD' variable. This should be used for objects
determined by configure
. Again from cpio
:
libcpio_a_LIBADD = @LIBOBJS@ @ALLOCA@ |
In addition, sources for extra objects that will not exist until
configure-time must be added to the BUILT_SOURCES
variable
(see section 10.4 Built sources).
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Building shared libraries is a relatively complex matter. For this reason, GNU Libtool (see section `Introduction' in The Libtool Manual) was created to help build shared libraries in a platform-independent way.
Automake uses Libtool to build libraries declared with the `LTLIBRARIES' primary. Each `_LTLIBRARIES' variable is a list of shared libraries to build. For instance, to create a library named `libgettext.a' and its corresponding shared libraries, and install them in `libdir', write:
lib_LTLIBRARIES = libgettext.la |
Note that shared libraries must be installed in order to work
properly, so check_LTLIBRARIES
is not allowed. However,
noinst_LTLIBRARIES
is allowed. This feature should be used for
libtool "convenience libraries".
For each library, the `library_LIBADD' variable contains the names of extra libtool objects (`.lo' files) to add to the shared library. The `library_LDFLAGS' variable contains any additional libtool flags, such as `-version-info' or `-static'.
Where an ordinary library might include @LIBOBJS@
, a libtool
library must use @LTLIBOBJS@
. This is required because the
object files that libtool operates on do not necessarily end in
`.o'. The libtool manual contains more details on this topic.
For libraries installed in some directory, Automake will automatically
supply the appropriate `-rpath' option. However, for libraries
determined at configure time (and thus mentioned in
EXTRA_LTLIBRARIES
), Automake does not know the eventual
installation directory; for such libraries you must add the
`-rpath' option to the appropriate `_LDFLAGS' variable by
hand.
Ordinarily, Automake requires that a shared library's name start with
`lib'. However, if you are building a dynamically loadable module
then you might wish to use a "nonstandard" name. In this case, put
-module
into the `_LDFLAGS' variable.
See section `The Libtool Manual' in The Libtool Manual, for more information.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Associated with each program are a collection of variables which can be used to modify how that program is built. There is a similar list of such variables for each library. The canonical name of the program (or library) is used as a base for naming these variables.
In the list below, we use the name "maude" to refer to the program or library. In your `Makefile.am' you would replace this with the canonical name of your program. This list also refers to "maude" as a program, but in general the same rules apply for both static and dynamic libraries; the documentation below notes situations where programs and libraries differ.
The prefixes `dist_' and `nodist_' can be used to control whether files listed in a `_SOURCES' variable are distributed. `dist_' is redundant, as sources are distributed by default, but it can be specified for clarity if desired.
It is possible to have both `dist_' and `nodist_' variants of a given `_SOURCES' variable at once; this lets you easily distribute some files and not others, for instance:
nodist_maude_SOURCES = nodist.c dist_maude_SOURCES = dist-me.c |
By default the output file (on Unix systems, the `.o' file) will be
put into the current build directory. However, if the option
subdir-objects
is in effect in the current directory then the
`.o' file will be put into the subdirectory named after the source
file. For instance, with subdir-objects
enabled,
`sub/dir/file.c' will be compiled to `sub/dir/file.o'. Some
people prefer this mode of operation. You can specify
subdir-objects
in AUTOMAKE_OPTIONS
(see section 17. Changing Automake's Behavior).
This variable also supports `dist_' and `nodist_' prefixes, e.g., `nodist_EXTRA_maude_SOURCES'.
$(AR) cru
followed by the name of the library and then the objects being put into
the library. You can override this by setting the `_AR' variable.
This is usually used with C++; some C++ compilers require a special
invocation in order to instantiate all the templates which should go
into a library. For instance, the SGI C++ compiler likes this variable set
like so:
libmaude_a_AR = $(CXX) -ar -o |
configure
.
configure
.
`_LDADD' and `_LIBADD' are inappropriate for passing program-specific linker flags (except for `-l', `-L', `-dlopen' and `-dlpreopen'). Use the `_LDFLAGS' variable for this purpose.
For instance, if your `configure.in' uses AC_PATH_XTRA
, you
could link your program against the X libraries like so:
maude_LDADD = $(X_PRE_LIBS) $(X_LIBS) $(X_EXTRA_LIBS) |
maude_LINK = $(CCLD) -magic -o $@ |
When using a per-program compilation flag, Automake will choose a different name for the intermediate object files. Ordinarily a file like `sample.c' will be compiled to produce `sample.o'. However, if the program's `_CFLAGS' variable is set, then the object file will be named, for instance, `maude-sample.o'.
In compilations with per-program flags, the ordinary `AM_' form of the flags variable is not automatically included in the compilation (however, the user form of the variable is included). So for instance, if you want the hypothetical `maude' compilations to also use the value of `AM_CFLAGS', you would need to write:
maude_CFLAGS = ... your flags ... $(AM_CFLAGS) |
If `_DEPENDENCIES' is not supplied, it is computed by Automake. The automatically-assigned value is the contents of `_LDADD' or `_LIBADD', with most configure substitutions, `-l', `-L', `-dlopen' and `-dlpreopen' options removed. The configure substitutions that are left in are only `@LIBOBJS@' and `@ALLOCA@'; these are left because it is known that they will not cause an invalid value for `_DEPENDENCIES' to be generated.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake explicitly recognizes the use of @LIBOBJS@
and
@ALLOCA@
, and uses this information, plus the list of
LIBOBJS
files derived from `configure.in' to automatically
include the appropriate source files in the distribution (see section 15. What Goes in a Distribution).
These source files are also automatically handled in the
dependency-tracking scheme; see See section 9.14 Automatic dependency tracking.
@LIBOBJS@
and @ALLOCA@
are specially recognized in any
`_LDADD' or `_LIBADD' variable.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Occasionally it is useful to know which `Makefile' variables Automake uses for compilations; for instance you might need to do your own compilation in some special cases.
Some variables are inherited from Autoconf; these are CC
,
CFLAGS
, CPPFLAGS
, DEFS
, LDFLAGS
, and
LIBS
.
There are some additional variables which Automake itself defines:
AM_CPPFLAGS
Automake already provides some `-I' options automatically. In
particular it generates `-I$(srcdir)', `-I.', and a `-I'
pointing to the directory holding `config.h' (if you've used
AC_CONFIG_HEADERS
or AM_CONFIG_HEADER
). You can disable
the default `-I' options using the `nostdinc' option.
AM_CPPFLAGS
is ignored in preference to a per-executable (or
per-library) _CPPFLAGS
variable if it is defined.
INCLUDES
AM_CFLAGS
_CFLAGS
.
COMPILE
AM_LDFLAGS
_LDFLAGS
.
LINK
CFLAGS
); it takes as "arguments" the names of the object files
and libraries to link in.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake has somewhat idiosyncratic support for Yacc and Lex.
Automake assumes that the `.c' file generated by yacc
(or
lex
) should be named using the basename of the input file. That
is, for a yacc source file `foo.y', Automake will cause the
intermediate file to be named `foo.c' (as opposed to
`y.tab.c', which is more traditional).
The extension of a yacc source file is used to determine the extension of the resulting `C' or `C++' file. Files with the extension `.y' will be turned into `.c' files; likewise, `.yy' will become `.cc'; `.y++', `c++'; and `.yxx', `.cxx'.
Likewise, lex source files can be used to generate `C' or `C++'; the extensions `.l', `.ll', `.l++', and `.lxx' are recognized.
You should never explicitly mention the intermediate (`C' or `C++') file in any `SOURCES' variable; only list the source file.
The intermediate files generated by yacc
(or lex
) will be
included in any distribution that is made. That way the user doesn't
need to have yacc
or lex
.
If a yacc
source file is seen, then your `configure.in' must
define the variable `YACC'. This is most easily done by invoking
the macro `AC_PROG_YACC' (see section `Particular Program Checks' in The Autoconf Manual).
When yacc
is invoked, it is passed `YFLAGS' and
`AM_YFLAGS'. The former is a user variable and the latter is
intended for the `Makefile.am' author.
Similarly, if a lex
source file is seen, then your
`configure.in' must define the variable `LEX'. You can use
`AC_PROG_LEX' to do this (see section `Particular Program Checks' in The Autoconf Manual), but using
AM_PROG_LEX
macro (see section 5.6 Autoconf macros supplied with Automake) is recommended.
When lex
is invoked, it is passed `LFLAGS' and
`AM_LFLAGS'. The former is a user variable and the latter is
intended for the `Makefile.am' author.
Automake makes it possible to include multiple yacc
(or
lex
) source files in a single program. When there is more than
one distinct yacc
(or lex
) source file in a directory,
Automake uses a small program called ylwrap
to run yacc
(or lex
) in a subdirectory. This is necessary because yacc's
output filename is fixed, and a parallel make could conceivably invoke
more than one instance of yacc
simultaneously. The ylwrap
program is distributed with Automake. It should appear in the directory
specified by `AC_CONFIG_AUX_DIR' (see section `Finding `configure' Input' in The Autoconf Manual), or the current
directory if that macro is not used in `configure.in'.
For yacc
, simply managing locking is insufficient. The output of
yacc
always uses the same symbol names internally, so it isn't
possible to link two yacc
parsers into the same executable.
We recommend using the following renaming hack used in gdb
:
#define yymaxdepth c_maxdepth #define yyparse c_parse #define yylex c_lex #define yyerror c_error #define yylval c_lval #define yychar c_char #define yydebug c_debug #define yypact c_pact #define yyr1 c_r1 #define yyr2 c_r2 #define yydef c_def #define yychk c_chk #define yypgo c_pgo #define yyact c_act #define yyexca c_exca #define yyerrflag c_errflag #define yynerrs c_nerrs #define yyps c_ps #define yypv c_pv #define yys c_s #define yy_yys c_yys #define yystate c_state #define yytmp c_tmp #define yyv c_v #define yy_yyv c_yyv #define yyval c_val #define yylloc c_lloc #define yyreds c_reds #define yytoks c_toks #define yylhs c_yylhs #define yylen c_yylen #define yydefred c_yydefred #define yydgoto c_yydgoto #define yysindex c_yysindex #define yyrindex c_yyrindex #define yygindex c_yygindex #define yytable c_yytable #define yycheck c_yycheck #define yyname c_yyname #define yyrule c_yyrule |
For each define, replace the `c_' prefix with whatever you like.
These defines work for bison
, byacc
, and traditional
yacc
s. If you find a parser generator that uses a symbol not
covered here, please report the new name so it can be added to the list.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake includes full support for C++.
Any package including C++ code must define the output variable
`CXX' in `configure.in'; the simplest way to do this is to use
the AC_PROG_CXX
macro (see section `Particular Program Checks' in The Autoconf Manual).
A few additional variables are defined when a C++ source file is seen:
CXX
CXXFLAGS
AM_CXXFLAGS
CXXFLAGS
.
CXXCOMPILE
CXXLINK
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake includes some support for assembly code.
The variable CCAS
holds the name of the compiler used to build
assembly code. This compiler must work a bit like a C compiler; in
particular it must accept `-c' and `-o'. The value of
CCASFLAGS
is passed to the compilation.
You are required to set CCAS
and CCASFLAGS
via
`configure.in'. The autoconf macro AM_PROG_AS
will do this
for you. Unless they are already set, it simply sets CCAS
to the
C compiler and CCASFLAGS
to the C compiler flags.
Only the suffixes `.s' and `.S' are recognized by
automake
as being files containing assembly code.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake includes full support for Fortran 77.
Any package including Fortran 77 code must define the output variable
`F77' in `configure.in'; the simplest way to do this is to use
the AC_PROG_F77
macro (see section `Particular Program Checks' in The Autoconf Manual). See section 9.10.4 Fortran 77 and Autoconf.
A few additional variables are defined when a Fortran 77 source file is seen:
F77
FFLAGS
AM_FFLAGS
FFLAGS
.
RFLAGS
AM_RFLAGS
RFLAGS
.
F77COMPILE
FLINK
Automake can handle preprocessing Fortran 77 and Ratfor source files in addition to compiling them(6). Automake also contains some support for creating programs and shared libraries that are a mixture of Fortran 77 and other languages (see section 9.10.3 Mixing Fortran 77 With C and C++).
These issues are covered in the following sections.
9.10.1 Preprocessing Fortran 77 9.10.2 Compiling Fortran 77 Files 9.10.3 Mixing Fortran 77 With C and C++ 9.10.4 Fortran 77 and Autoconf
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
`N.f' is made automatically from `N.F' or `N.r'. This rule runs just the preprocessor to convert a preprocessable Fortran 77 or Ratfor source file into a strict Fortran 77 source file. The precise command used is as follows:
$(F77) -F $(DEFS) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_FFLAGS) $(FFLAGS)
$(F77) -F $(AM_FFLAGS) $(FFLAGS) $(AM_RFLAGS) $(RFLAGS)
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
`N.o' is made automatically from `N.f', `N.F' or `N.r' by running the Fortran 77 compiler. The precise command used is as follows:
$(F77) -c $(AM_FFLAGS) $(FFLAGS)
$(F77) -c $(DEFS) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_FFLAGS) $(FFLAGS)
$(F77) -c $(AM_FFLAGS) $(FFLAGS) $(AM_RFLAGS) $(RFLAGS)
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake currently provides limited support for creating programs and shared libraries that are a mixture of Fortran 77 and C and/or C++. However, there are many other issues related to mixing Fortran 77 with other languages that are not (currently) handled by Automake, but that are handled by other packages(7).
Automake can help in two ways:
These extra Fortran 77 linker flags are supplied in the output variable
FLIBS
by the AC_F77_LIBRARY_LDFLAGS
Autoconf macro
supplied with newer versions of Autoconf (Autoconf version 2.13 and
later). See section `Fortran 77 Compiler Characteristics' in The Autoconf.
If Automake detects that a program or shared library (as mentioned in
some _PROGRAMS
or _LTLIBRARIES
primary) contains source
code that is a mixture of Fortran 77 and C and/or C++, then it requires
that the macro AC_F77_LIBRARY_LDFLAGS
be called in
`configure.in', and that either $(FLIBS)
or @FLIBS@
appear in the appropriate _LDADD
(for programs) or _LIBADD
(for shared libraries) variables. It is the responsibility of the
person writing the `Makefile.am' to make sure that $(FLIBS)
or @FLIBS@
appears in the appropriate _LDADD
or
_LIBADD
variable.
For example, consider the following `Makefile.am':
bin_PROGRAMS = foo foo_SOURCES = main.cc foo.f foo_LDADD = libfoo.la @FLIBS@ pkglib_LTLIBRARIES = libfoo.la libfoo_la_SOURCES = bar.f baz.c zardoz.cc libfoo_la_LIBADD = $(FLIBS) |
In this case, Automake will insist that AC_F77_LIBRARY_LDFLAGS
is mentioned in `configure.in'. Also, if @FLIBS@
hadn't
been mentioned in foo_LDADD
and libfoo_la_LIBADD
, then
Automake would have issued a warning.
9.10.3.1 How the Linker is Chosen
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
The following diagram demonstrates under what conditions a particular linker is chosen by Automake.
For example, if Fortran 77, C and C++ source code were to be compiled
into a program, then the C++ linker will be used. In this case, if the
C or Fortran 77 linkers required any special libraries that weren't
included by the C++ linker, then they must be manually added to an
_LDADD
or _LIBADD
variable by the user writing the
`Makefile.am'.
\ Linker source \ code \ C C++ Fortran ----------------- +---------+---------+---------+ | | | | C | x | | | | | | | +---------+---------+---------+ | | | | C++ | | x | | | | | | +---------+---------+---------+ | | | | Fortran | | | x | | | | | +---------+---------+---------+ | | | | C + C++ | | x | | | | | | +---------+---------+---------+ | | | | C + Fortran | | | x | | | | | +---------+---------+---------+ | | | | C++ + Fortran | | x | | | | | | +---------+---------+---------+ | | | | C + C++ + Fortran | | x | | | | | | +---------+---------+---------+ |
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
The current Automake support for Fortran 77 requires a recent enough version of Autoconf that also includes support for Fortran 77. Full Fortran 77 support was added to Autoconf 2.13, so you will want to use that version of Autoconf or later.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake includes support for compiled Java, using gcj
, the Java
front end to the GNU Compiler Collection.
Any package including Java code to be compiled must define the output
variable `GCJ' in `configure.in'; the variable `GCJFLAGS'
must also be defined somehow (either in `configure.in' or
`Makefile.am'). The simplest way to do this is to use the
AM_PROG_GCJ
macro.
By default, programs including Java source files are linked with
gcj
.
As always, the contents of `AM_GCJFLAGS' are passed to every
compilation invoking gcj
(in its role as an ahead-of-time
compiler -- when invoking it to create `.class' files,
`AM_JAVACFLAGS' is used instead). If it is necessary to pass
options to gcj
from `Makefile.am', this variable, and not
the user variable `GCJFLAGS', should be used.
gcj
can be used to compile `.java', `.class',
`.zip', or `.jar' files.
When linking, gcj
requires that the main class be specified
using the `--main=' option. The easiest way to do this is to use
the _LDFLAGS
variable for the program.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake currently only includes full support for C, C++ (see section 9.8 C++ Support), Fortran 77 (see section 9.10 Fortran 77 Support), and Java (see section 9.11 Java Support). There is only rudimentary support for other languages, support for which will be improved based on user demand.
Some limited support for adding your own languages is available via the suffix rule handling; see 18.2 Handling new file extensions.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Although the GNU standards allow the use of ANSI C, this can have the effect of limiting portability of a package to some older compilers (notably the SunOS C compiler).
Automake allows you to work around this problem on such machines by de-ANSI-fying each source file before the actual compilation takes place.
If the `Makefile.am' variable AUTOMAKE_OPTIONS
(see section 17. Changing Automake's Behavior) contains the option ansi2knr
then code to
handle de-ANSI-fication is inserted into the generated
`Makefile.in'.
This causes each C source file in the directory to be treated as ANSI C.
If an ANSI C compiler is available, it is used. If no ANSI C compiler
is available, the ansi2knr
program is used to convert the source
files into K&R C, which is then compiled.
The ansi2knr
program is simple-minded. It assumes the source
code will be formatted in a particular way; see the ansi2knr
man
page for details.
Support for de-ANSI-fication requires the source files `ansi2knr.c'
and `ansi2knr.1' to be in the same package as the ANSI C source;
these files are distributed with Automake. Also, the package
`configure.in' must call the macro AM_C_PROTOTYPES
(see section 5.6 Autoconf macros supplied with Automake).
Automake also handles finding the ansi2knr
support files in some
other directory in the current package. This is done by prepending the
relative path to the appropriate directory to the ansi2knr
option. For instance, suppose the package has ANSI C code in the
`src' and `lib' subdirs. The files `ansi2knr.c' and
`ansi2knr.1' appear in `lib'. Then this could appear in
`src/Makefile.am':
AUTOMAKE_OPTIONS = ../lib/ansi2knr |
If no directory prefix is given, the files are assumed to be in the current directory.
Files mentioned in LIBOBJS
which need de-ANSI-fication will not
be automatically handled. That's because configure
will generate
an object name like `regex.o', while make
will be looking
for `regex_.o' (when de-ANSI-fying). Eventually this problem will
be fixed via autoconf
magic, but for now you must put this code
into your `configure.in', just before the AC_OUTPUT
call:
# This is necessary so that .o files in LIBOBJS are also built via # the ANSI2KNR-filtering rules. LIBOBJS=`echo $LIBOBJS|sed 's/\.o /\$U.o /g;s/\.o$/\$U.o/'` |
Note that automatic de-ANSI-fication will not work when the package is
being built for a different host architecture. That is because automake
currently has no way to build ansi2knr
for the build machine.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
As a developer it is often painful to continually update the `Makefile.in' whenever the include-file dependencies change in a project. Automake supplies a way to automatically track dependency changes.
Automake always uses complete dependencies for a compilation, including
system headers. Automake's model is that dependency computation should
be a side effect of the build. To this end, dependencies are computed
by running all compilations through a special wrapper program called
depcomp
. depcomp
understands how to coax many different C
and C++ compilers into generating dependency information in the format
it requires. automake -a
will install depcomp
into your
source tree for you. If depcomp
can't figure out how to properly
invoke your compiler, dependency tracking will simply be disabled for
your build.
Experience with earlier versions of Automake (8) taught us that it is not reliable to generate dependencies only on the maintainer's system, as configurations vary too much. So instead Automake implements dependency tracking at build time.
Automatic dependency tracking can be suppressed by putting
no-dependencies
in the variable AUTOMAKE_OPTIONS
, or
passing no-dependencies
as an argument to AM_INIT_AUTOMAKE
(this should be the prefered way). Or, you can invoke automake
with the -i
option. Dependency tracking is enabled by default.
The person building your package also can choose to disable dependency
tracking by configuring with --disable-dependency-tracking
.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
On some platforms, such as Windows, executables are expected to have an extension such as `.exe'. On these platforms, some compilers (GCC among them) will automatically generate `foo.exe' when asked to generate `foo'.
Automake provides mostly-transparent support for this. Unfortunately mostly doesn't yet mean fully. Until the English dictionary is revised, you will have to assist Automake if your package must support those platforms.
One thing you must be aware of is that, internally, Automake rewrites something like this:
bin_PROGRAMS = liver |
to this:
bin_PROGRAMS = liver$(EXEEXT) |
The targets Automake generates are likewise given the `$(EXEEXT)'
extension. EXEEXT
However, Automake cannot apply this rewriting to configure
substitutions. This means that if you are conditionally building a
program using such a substitution, then your `configure.in' must
take care to add `$(EXEEXT)' when constructing the output variable.
With Autoconf 2.13 and earlier, you must explicitly use AC_EXEEXT
to get this support. With Autoconf 2.50, AC_EXEEXT
is run
automatically if you configure a compiler (say, through
AC_PROG_CC
).
Sometimes maintainers like to write an explicit link rule for their program. Without executable extension support, this is easy--you simply write a target with the same name as the program. However, when executable extension support is enabled, you must instead add the `$(EXEEXT)' suffix.
Unfortunately, due to the change in Autoconf 2.50, this means you must
always add this extension. However, this is a problem for maintainers
who know their package will never run on a platform that has executable
extensions. For those maintainers, the no-exeext
option
(see section 17. Changing Automake's Behavior) will disable this feature. This works in a fairly
ugly way; if no-exeext
is seen, then the presence of a target
named foo
in `Makefile.am' will override an
automake-generated target of the form foo$(EXEEXT)
. Without the
no-exeext
option, this use will give an error.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake can handle derived objects which are not C programs. Sometimes the support for actually building such objects must be explicitly supplied, but Automake will still automatically handle installation and distribution.
10.1 Executable Scripts Executable scripts 10.2 Header files 10.3 Architecture-independent data files 10.4 Built sources Derived sources
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
It is possible to define and install programs which are scripts. Such programs are listed using the `SCRIPTS' primary name. Automake doesn't define any dependencies for scripts; the `Makefile.am' should include the appropriate rules.
Automake does not assume that scripts are derived objects; such objects must be deleted by hand (see section 14. What Gets Cleaned).
The automake
program itself is a Perl script that is generated at
configure time from `automake.in'. Here is how this is handled:
bin_SCRIPTS = automake |
Since automake
appears in the AC_OUTPUT
macro, a target
for it is automatically generated, and it is also automatically cleaned
(despite the fact it's a script).
Script objects can be installed in bindir
, sbindir
,
libexecdir
, or pkgdatadir
.
Scripts that need not being installed can be listed in
noinst_SCRIPTS
, and among them, those which are needed only by
make check
should go in check_SCRIPTS
.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Header files are specified by the `HEADERS' family of variables.
Generally header files are not installed, so the noinst_HEADERS
variable will be the most used. (9)
All header files must be listed somewhere; missing ones will not appear in the distribution. Often it is clearest to list uninstalled headers with the rest of the sources for a program. See section 9.1 Building a program. Headers listed in a `_SOURCES' variable need not be listed in any `_HEADERS' variable.
Headers can be installed in includedir
, oldincludedir
, or
pkgincludedir
.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake supports the installation of miscellaneous data files using the `DATA' family of variables.
Such data can be installed in the directories datadir
,
sysconfdir
, sharedstatedir
, localstatedir
, or
pkgdatadir
.
By default, data files are not included in a distribution. Of course, you can use the `dist_' prefix to change this on a per-variable basis.
Here is how Automake declares its auxiliary data files:
dist_pkgdata_DATA = clean-kr.am clean.am ... |
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Because Automake's automatic dependency tracking works as a side-effect of compilation (see section 9.14 Automatic dependency tracking) there is a bootstrap issue: a target should not be compiled before its dependencies are made, but these dependencies are unknown until the target is first compiled.
Ordinarily this is not a problem, because dependencies are distributed
sources: they preexist and do not need to be built. Suppose that
`foo.c' includes `foo.h'. When it first compiles
`foo.o', make
only knows that `foo.o' depends on
`foo.c'. As a side-effect of this compilation depcomp
records the `foo.h' dependency so that following invocations of
make
will honor it. In these conditions, it's clear there is
no problem: either `foo.o' doesn't exist and has to be built
(regardless of the dependencies), either accurate dependencies exist and
they can be used to decide whether `foo.o' should be rebuilt.
It's a different story if `foo.h' doesn't exist by the first
make
run. For instance there might be a rule to build
`foo.h'. This time `file.o''s build will fail because the
compiler can't find `foo.h'. make
failed to trigger the
rule to build `foo.h' first by lack of dependency information.
The BUILT_SOURCES
variable is a workaround for this problem. A
source file listed in BUILT_SOURCES
is made on make all
or
make check
before other targets are processed. However, such a
source file is not compiled unless explicitly requested by
mentioning it in some other `_SOURCES' variable.
So, to conclude our introductory example, we could use
BUILT_SOURCES = foo.h
to ensure `foo.h' gets built before
any other target (including `foo.o') during make all
or
make check
.
BUILT_SOURCES
is actually a bit of a misnomer, as any file which
must be created early in the build process can be listed in this
variable. Moreover, all built sources do not necessarily have to be
listed in BUILT_SOURCES
. For instance a generated `.c' file
doesn't need to appear in BUILT_SOURCES
(unless it is included by
another source), because it's a known dependency of the associated
object.
It might be important to emphasize that BUILT_SOURCES
is honored
only by make all
and make check
. This means you cannot
build a specific target (e.g., make foo
) in a clean tree if it
depends on a built source. However if it will succeed if you have run
make all
earlier, because accurate dependencies are already
available.
The next section illustrates and discusses the handling of built sources on a toy example.
10.4.1 Built sources example Several ways to handle built sources.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Suppose that `foo.c' includes `bindir.h', which is
installation-dependent and not distributed: it needs to be built. Here
`bindir.h' defines the preprocessor macro bindir
to the
value of the make
variable bindir
(inherited from
`configure').
We suggest several implementations below. It's not meant to be an exhaustive listing of all ways to handle built sources, but it will give you a few ideas if you encounter this issue.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
This first implementation will illustrate the bootstrap issue mentioned in the previous section (see section 10.4 Built sources).
Here is a tentative `Makefile.am'.
# This won't work. bin_PROGRAMS = foo foo_SOURCES = foo.c nodist_foo_SOURCES = bindir.h CLEANFILES = bindir.h bindir.h: Makefile echo '#define bindir "$(bindir)"' >$@ |
This setup doesn't work, because Automake doesn't know that `foo.c' includes `bindir.h'. Remember, automatic dependency tracking works as a side-effect of compilation, so the dependencies of `foo.o' will be known only after `foo.o' has been compiled (see section 9.14 Automatic dependency tracking). The symptom is as follows.
% make source='foo.c' object='foo.o' libtool=no \ depfile='.deps/foo.Po' tmpdepfile='.deps/foo.TPo' \ depmode=gcc /bin/sh ./depcomp \ gcc -I. -I. -g -O2 -c `test -f 'foo.c' || echo './'`foo.c foo.c:2: bindir.h: No such file or directory make: *** [foo.o] Error 1 |
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
BUILT_SOURCES
A solution is to require `bindir.h' to be built before anything
else. This is what BUILT_SOURCES
is meant for (see section 10.4 Built sources).
bin_PROGRAMS = foo foo_SOURCES = foo.c BUILT_SOURCES = bindir.h CLEANFILES = bindir.h bindir.h: Makefile echo '#define bindir "$(bindir)"' >$@ |
See how `bindir.h' get built first:
% make echo '#define bindir "/usr/local/bin"' >bindir.h make all-am make[1]: Entering directory `/home/adl/tmp' source='foo.c' object='foo.o' libtool=no \ depfile='.deps/foo.Po' tmpdepfile='.deps/foo.TPo' \ depmode=gcc /bin/sh ./depcomp \ gcc -I. -I. -g -O2 -c `test -f 'foo.c' || echo './'`foo.c gcc -g -O2 -o foo foo.o make[1]: Leaving directory `/home/adl/tmp' |
However, as said earlier, BUILT_SOURCES
applies only to the
all
and check
targets. It still fails if you try to run
make foo
explicitly:
% make clean test -z "bindir.h" || rm -f bindir.h test -z "foo" || rm -f foo rm -f *.o core *.core % : > .deps/foo.Po # Suppress previously recorded dependencies % make foo source='foo.c' object='foo.o' libtool=no \ depfile='.deps/foo.Po' tmpdepfile='.deps/foo.TPo' \ depmode=gcc /bin/sh ./depcomp \ gcc -I. -I. -g -O2 -c `test -f 'foo.c' || echo './'`foo.c foo.c:2: bindir.h: No such file or directory make: *** [foo.o] Error 1 |
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Usually people are happy enough with BUILT_SOURCES
because they
never run targets such as make foo
before make all
, as in
the previous example. However if this matters to you, you can avoid
BUILT_SOURCES
and record such dependencies explicitly in the
`Makefile.am'.
bin_PROGRAMS = foo foo_SOURCES = foo.c foo.$(OBJEXT): bindir.h CLEANFILES = bindir.h bindir.h: Makefile echo '#define bindir "$(bindir)"' >$@ |
You don't have to list all the dependencies of foo.o
explicitly, only those which might need to be built. If a dependency
already exists, it will not hinder the first compilation and will be
recorded by the normal dependency tracking code. (Note that after this
first compilation the dependency tracking code will also have recorded
the dependency between foo.o
and bindir.h
; so our explicit
dependency is really useful to the first build only.)
Adding explicit dependencies like this can be a bit dangerous if you are
not careful enough. This is due to the way Automake tries not to
overwrite your rules (it assumes you know better than it).
foo.$(OBJEXT): bindir.h
supersedes any rule Automake may want to
output to build foo.$(OBJEXT)
. It happens to work in this case
because Automake doesn't have to output any foo.$(OBJEXT):
target: it relies on a suffix rule instead (i.e., .c.$(OBJEXT):
).
Always check the generated `Makefile.in' if you do this.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
It's possible to define this preprocessor macro from `configure',
either in `config.h' (see section `Defining Directories' in The Autoconf Manual), or by processing a
`bindir.h.in' file using AC_CONFIG_FILES
(see section `Configuration Actions' in The Autoconf Manual).
At this point it should be clear that building `bindir.h' from `configure' work well for this example. `bindir.h' will exist before you build any target, hence will not cause any dependency issue.
The Makefile can be shrunk as follows. We do not even have to mention `bindir.h'.
bin_PROGRAMS = foo foo_SOURCES = foo.c |
However, it's not always possible to build sources from `configure', especially when these sources are generated by a tool that needs to be built first...
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Another attractive idea is to define bindir
as a variable or
function exported from `bindir.o', and build `bindir.c'
instead of `bindir.h'.
noinst_PROGRAMS = foo foo_SOURCES = foo.c bindir.h nodist_foo_SOURCES = bindir.c CLEANFILES = bindir.c bindir.c: Makefile echo 'const char bindir[] = "$(bindir)";' >$ |
`bindir.h' contains just the variable's declaration and doesn't need to be built, so it won't cause any trouble. `bindir.o' is always dependent on `bindir.c', so `bindir.c' will get built first.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
There is no panacea, of course. Each solution has its merits and drawbacks.
You cannot use BUILT_SOURCES
if the ability to run make
foo
on a clean tree is important to you.
You won't add explicit dependencies if you are leery of overriding an Automake target by mistake.
Building files from `./configure' is not always possible, neither is converting `.h' files into `.c' files.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Since Automake is primarily intended to generate `Makefile.in's for use in GNU programs, it tries hard to interoperate with other GNU tools.
11.1 Emacs Lisp 11.2 Gettext 11.3 Libtool 11.4 Java 11.5 Python
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake provides some support for Emacs Lisp. The `LISP' primary
is used to hold a list of `.el' files. Possible prefixes for this
primary are `lisp_' and `noinst_'. Note that if
lisp_LISP
is defined, then `configure.in' must run
AM_PATH_LISPDIR
(see section 5.6 Autoconf macros supplied with Automake).
By default Automake will byte-compile all Emacs Lisp source files using
the Emacs found by AM_PATH_LISPDIR
. If you wish to avoid
byte-compiling, simply define the variable ELCFILES
to be empty.
Byte-compiled Emacs Lisp files are not portable among all versions of
Emacs, so it makes sense to turn this off if you expect sites to have
more than one version of Emacs installed. Furthermore, many packages
don't actually benefit from byte-compilation. Still, we recommend that
you leave it enabled by default. It is probably better for sites with
strange setups to cope for themselves than to make the installation less
nice for everybody else.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
If AM_GNU_GETTEXT
is seen in `configure.in', then Automake
turns on support for GNU gettext, a message catalog system for
internationalization
(see section `GNU Gettext' in GNU gettext utilities).
The gettext
support in Automake requires the addition of two
subdirectories to the package, `intl' and `po'. Automake
insures that these directories exist and are mentioned in
SUBDIRS
.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake provides support for GNU Libtool (see section `Introduction' in The Libtool Manual) with the `LTLIBRARIES' primary. See section 9.3 Building a Shared Library.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake provides some minimal support for Java compilation with the `JAVA' primary.
Any `.java' files listed in a `_JAVA' variable will be
compiled with JAVAC
at build time. By default, `.class'
files are not included in the distribution.
Currently Automake enforces the restriction that only one `_JAVA' primary can be used in a given `Makefile.am'. The reason for this restriction is that, in general, it isn't possible to know which `.class' files were generated from which `.java' files -- so it would be impossible to know which files to install where. For instance, a `.java' file can define multiple classes; the resulting `.class' file names cannot be predicted without parsing the `.java' file.
There are a few variables which are used when compiling Java sources:
JAVAC
JAVACFLAGS
AM_JAVACFLAGS
JAVACFLAGS
, should be used when it is necessary to put Java
compiler flags into `Makefile.am'.
JAVAROOT
javac
. It defaults to `$(top_builddir)'.
CLASSPATH_ENV
sh
expression which is used to set the
CLASSPATH
environment variable on the javac
command line.
(In the future we will probably handle class path setting differently.)
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake provides support for Python compilation with the `PYTHON' primary.
Any files listed in a `_PYTHON' variable will be byte-compiled with
py-compile
at install time. py-compile
actually creates
both standard (`.pyc') and byte-compiled (`.pyo') versions of
the source files. Note that because byte-compilation occurs at install
time, any files listed in `noinst_PYTHON' will not be compiled.
Python source files are included in the distribution by default.
Automake ships with an Autoconf macro called AM_PATH_PYTHON
which
will determine some Python-related directory variables (see below). If
you have called AM_PATH_PYTHON
from `configure.in', then you
may use the following variables to list you Python source files in your
variables: `python_PYTHON', `pkgpython_PYTHON',
`pyexecdir_PYTHON', `pkgpyexecdir_PYTHON', depending where you
want your files installed.
AM_PATH_PYTHON
takes a single optional argument. This argument,
if present, is the minimum version of Python which can be used for this
package. If the version of Python found on the system is older than the
required version, then AM_PATH_PYTHON
will cause an error.
AM_PATH_PYTHON
creates several output variables based on the
Python installation found during configuration.
PYTHON
PYTHON_VERSION
sys.version[:3]
.
PYTHON_PREFIX
$prefix
. This term may be used in future work
which needs the contents of Python's sys.prefix
, but general
consensus is to always use the value from configure.
PYTHON_EXEC_PREFIX
$exec_prefix
. This term may be used in future work
which needs the contents of Python's sys.exec_prefix
, but general
consensus is to always use the value from configure.
PYTHON_PLATFORM
sys.platform
. This value is sometimes needed when
building Python extensions.
pythondir
pkgpythondir
pythondir
which is named after the
package. That is, it is `$(pythondir)/$(PACKAGE)'. It is provided
as a convenience.
pyexecdir
pkgpyexecdir
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Currently Automake provides support for Texinfo and man pages.
12.1 Texinfo 12.2 Man pages
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
If the current directory contains Texinfo source, you must declare it
with the `TEXINFOS' primary. Generally Texinfo files are converted
into info, and thus the info_TEXINFOS
variable is most commonly used
here. Any Texinfo source file must end in the `.texi',
`.txi', or `.texinfo' extension. We recommend `.texi'
for new manuals.
Automake generates rules to build `.info', `.dvi', `.ps',
and `.pdf' files from your Texinfo sources. The `.info' files
are built by make all
and installed by make install
(unless you use no-installinfo
, see below). The other files can
be built on request by make dvi
, make ps
, and make
pdf
.
If the `.texi' file @include
s `version.texi', then
that file will be automatically generated. The file `version.texi'
defines four Texinfo flag you can reference using
@value{EDITION}
, @value{VERSION}
,
@value{UPDATED}
, and @value{UPDATED-MONTH}
.
EDITION
VERSION
UPDATED
UPDATED-MONTH
The `version.texi' support requires the mdate-sh
program;
this program is supplied with Automake and automatically included when
automake
is invoked with the --add-missing
option.
If you have multiple Texinfo files, and you want to use the `version.texi' feature, then you have to have a separate version file for each Texinfo file. Automake will treat any include in a Texinfo file that matches `vers*.texi' just as an automatically generated version file.
When an info file is rebuilt, the program named by the MAKEINFO
variable is used to invoke it. If the makeinfo
program is found
on the system then it will be used by default; otherwise missing
will be used instead. The flags in the variables MAKEINFOFLAGS
and AM_MAKEINFOFLAGS
will be passed to the makeinfo
invocation; the first of these is intended for use by the user
(see section 2.5 Variables reserved for the user) and the second by the `Makefile.am'
writer.
Sometimes an info file actually depends on more than one `.texi'
file. For instance, in GNU Hello, `hello.texi' includes the file
`gpl.texi'. You can tell Automake about these dependencies using
the texi_TEXINFOS
variable. Here is how GNU Hello does it:
info_TEXINFOS = hello.texi hello_TEXINFOS = gpl.texi |
By default, Automake requires the file `texinfo.tex' to appear in
the same directory as the Texinfo source. However, if you used
AC_CONFIG_AUX_DIR
in `configure.in' (see section `Finding `configure' Input' in The Autoconf Manual), then
`texinfo.tex' is looked for there. Automake supplies
`texinfo.tex' if `--add-missing' is given.
If your package has Texinfo files in many directories, you can use the
variable TEXINFO_TEX
to tell Automake where to find the canonical
`texinfo.tex' for your package. The value of this variable should
be the relative path from the current `Makefile.am' to
`texinfo.tex':
TEXINFO_TEX = ../doc/texinfo.tex |
The option `no-texinfo.tex' can be used to eliminate the
requirement for `texinfo.tex'. Use of the variable
TEXINFO_TEX
is preferable, however, because that allows the
dvi
, ps
, and pdf
targets to still work.
Automake generates an install-info
target; some people apparently
use this. By default, info pages are installed by `make install'.
This can be prevented via the no-installinfo
option.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
A package can also include man pages (but see the GNU standards on this
matter, section `Man Pages' in The GNU Coding Standards.) Man
pages are declared using the `MANS' primary. Generally the
man_MANS
variable is used. Man pages are automatically installed in
the correct subdirectory of mandir
, based on the file extension.
File extensions such as `.1c' are handled by looking for the valid
part of the extension and using that to determine the correct
subdirectory of mandir
. Valid section names are the digits
`0' through `9', and the letters `l' and `n'.
Sometimes developers prefer to name a man page something like `foo.man' in the source, and then rename it to have the correct suffix, e.g. `foo.1', when installing the file. Automake also supports this mode. For a valid section named SECTION, there is a corresponding directory named `manSECTIONdir', and a corresponding `_MANS' variable. Files listed in such a variable are installed in the indicated section. If the file already has a valid suffix, then it is installed as-is; otherwise the file suffix is changed to match the section.
For instance, consider this example:
man1_MANS = rename.man thesame.1 alsothesame.1c |
In this case, `rename.man' will be renamed to `rename.1' when installed, but the other files will keep their names.
By default, man pages are installed by `make install'. However,
since the GNU project does not require man pages, many maintainers do
not expend effort to keep the man pages up to date. In these cases, the
no-installman
option will prevent the man pages from being
installed by default. The user can still explicitly install them via
`make install-man'.
Here is how the man pages are handled in GNU cpio
(which includes
both Texinfo documentation and man pages):
man_MANS = cpio.1 mt.1 EXTRA_DIST = $(man_MANS) |
Man pages are not currently considered to be source, because it is not uncommon for man pages to be automatically generated. Therefore they are not automatically included in the distribution. However, this can be changed by use of the `dist_' prefix.
The `nobase_' prefix is meaningless for man pages and is disallowed.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Naturally, Automake handles the details of actually installing your
program once it has been built. All files named by the various
primaries are automatically installed in the appropriate places when the
user runs make install
.
A file named in a primary is installed by copying the built file into the appropriate directory. The base name of the file is used when installing.
bin_PROGRAMS = hello subdir/goodbye |
In this example, both `hello' and `goodbye' will be installed
in $(bindir)
.
Sometimes it is useful to avoid the basename step at install time. For instance, you might have a number of header files in subdirectories of the source tree which are laid out precisely how you want to install them. In this situation you can use the `nobase_' prefix to suppress the base name step. For example:
nobase_include_HEADERS = stdio.h sys/types.h |
Will install `stdio.h' in $(includedir)
and `types.h'
in $(includedir)/sys
.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake generates separate install-data
and install-exec
targets, in case the installer is installing on multiple machines which
share directory structure--these targets allow the machine-independent
parts to be installed only once. install-exec
installs
platform-dependent files, and install-data
installs
platform-independent files. The install
target depends on both
of these targets. While Automake tries to automatically segregate
objects into the correct category, the `Makefile.am' author is, in
the end, responsible for making sure this is done correctly.
Variables using the standard directory prefixes `data', `info', `man', `include', `oldinclude', `pkgdata', or `pkginclude' (e.g. `data_DATA') are installed by `install-data'.
Variables using the standard directory prefixes `bin', `sbin', `libexec', `sysconf', `localstate', `lib', or `pkglib' (e.g. `bin_PROGRAMS') are installed by `install-exec'.
Any variable using a user-defined directory prefix with `exec' in the name (e.g. `myexecbin_PROGRAMS' is installed by `install-exec'. All other user-defined prefixes are installed by `install-data'.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
It is possible to extend this mechanism by defining an
install-exec-local
or install-data-local
target. If these
targets exist, they will be run at `make install' time. These
rules can do almost anything; care is required.
Automake also supports two install hooks, install-exec-hook
and
install-data-hook
. These hooks are run after all other install
rules of the appropriate type, exec or data, have completed. So, for
instance, it is possible to perform post-installation modifications
using an install hook.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake generates support for the `DESTDIR' variable in all install rules. `DESTDIR' is used during the `make install' step to relocate install objects into a staging area. Each object and path is prefixed with the value of `DESTDIR' before being copied into the install area. Here is an example of typical DESTDIR usage:
make DESTDIR=/tmp/staging install |
This places install objects in a directory tree built under `/tmp/staging'. If `/gnu/bin/foo' and `/gnu/share/aclocal/foo.m4' are to be installed, the above command would install `/tmp/staging/gnu/bin/foo' and `/tmp/staging/gnu/share/aclocal/foo.m4'.
This feature is commonly used to build install images and packages. For more information, see section `Makefile Conventions' in The GNU Coding Standards.
Support for `DESTDIR' is implemented by coding it directly into the
install rules. If your `Makefile.am' uses a local install rule
(e.g., install-exec-local
) or an install hook, then you must
write that code to respect `DESTDIR'.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake also generates an uninstall
target, an
installdirs
target, and an install-strip
target.
Automake supports uninstall-local
and uninstall-hook
.
There is no notion of separate uninstalls for "exec" and "data", as
these features would not provide additional functionality.
Note that uninstall
is not meant as a replacement for a real
packaging tool.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
The GNU Makefile Standards specify a number of different clean rules. See See section `Standard Targets for Users' in The GNU Coding Standards.
Generally the files that can be cleaned are determined automatically by
Automake. Of course, Automake also recognizes some variables that can
be defined to specify additional files to clean. These variables are
MOSTLYCLEANFILES
, CLEANFILES
, DISTCLEANFILES
, and
MAINTAINERCLEANFILES
.
As the GNU Standards aren't always explicit as to which files should be removed by which target, we've adopted a heuristic which we believe was first formulated by François Pinard:
make
built it, and it is commonly something that one would
want to rebuild (for instance, a `.o' file), then
mostlyclean
should delete it.
make
built it, then clean
should delete it.
configure
built it, then distclean
should delete it
maintainer-clean
should
delete it.
We recommend that you follow this same set of heuristics in your `Makefile.am'.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
The dist
target in the generated `Makefile.in' can be used
to generate a gzip'd tar
file and other flavors of archive for
distribution. The files is named based on the `PACKAGE' and
`VERSION' variables defined by AM_INIT_AUTOMAKE
(see section 5.6 Autoconf macros supplied with Automake); more precisely the gzip'd tar
file is named
`package-version.tar.gz'.
You can use the make
variable `GZIP_ENV' to control how gzip
is run. The default setting is `--best'.
For the most part, the files to distribute are automatically found by
Automake: all source files are automatically included in a distribution,
as are all `Makefile.am's and `Makefile.in's. Automake also
has a built-in list of commonly used files which are automatically
included if they are found in the current directory (either physically,
or as the target of a `Makefile.am' rule). This list is printed by
`automake --help'. Also, files which are read by configure
(i.e. the source files corresponding to the files specified in various
Autoconf macros such as AC_CONFIG_FILES
and siblings) are
automatically distributed.
Still, sometimes there are files which must be distributed, but which
are not covered in the automatic rules. These files should be listed in
the EXTRA_DIST
variable. You can mention files from
subdirectories in EXTRA_DIST
.
You can also mention a directory in EXTRA_DIST
; in this case the
entire directory will be recursively copied into the distribution.
Please note that this will also copy everything in the directory,
including CVS/RCS version control files. We recommend against using
this feature.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Sometimes you need tighter control over what does not go into the distribution; for instance you might have source files which are generated and which you do not want to distribute. In this case Automake gives fine-grained control using the `dist' and `nodist' prefixes. Any primary or `_SOURCES' variable can be prefixed with `dist_' to add the listed files to the distribution. Similarly, `nodist_' can be used to omit the files from the distribution.
As an example, here is how you would cause some data to be distributed while leaving some source code out of the distribution:
dist_data_DATA = distribute-this bin_PROGRAMS = foo nodist_foo_SOURCES = do-not-distribute.c |
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Another way to to use this is for removing unnecessary files that get recursively included by specifying a directory in EXTRA_DIST:
EXTRA_DIST = doc dist-hook: rm -rf `find $(distdir)/doc -name CVS` |
If you define SUBDIRS
, Automake will recursively include the
subdirectories in the distribution. If SUBDIRS
is defined
conditionally (see section 20. Conditionals), Automake will normally include all
directories that could possibly appear in SUBDIRS
in the
distribution. If you need to specify the set of directories
conditionally, you can set the variable DIST_SUBDIRS
to the exact
list of subdirectories to include in the distribution.
Occasionally it is useful to be able to change the distribution before
it is packaged up. If the dist-hook
target exists, it is run
after the distribution directory is filled, but before the actual tar
(or shar) file is created. One way to use this is for distributing
files in subdirectories for which a new `Makefile.am' is overkill:
dist-hook: mkdir $(distdir)/random cp -p $(srcdir)/random/a1 $(srcdir)/random/a2 $(distdir)/random |
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake also generates a distcheck
target which can be of help
to ensure that a given distribution will actually work.
distcheck
makes a distribution, then tries to do a VPATH
build, run the testsuite, and finally make another tarfile to ensure the
distribution is self-contained.
Building the package involves running ./configure
. If you need
to supply additional flags to configure
, define them in the
DISTCHECK_CONFIGURE_FLAGS
variable, either in your top-level
`Makefile.am', or on the command line when invoking make
.
If the target distcheck-hook
is defined in your
`Makefile.am', then it will be invoked by distcheck
after
the new distribution has been unpacked, but before the unpacked copy is
configured and built. Your distcheck-hook
can do almost
anything, though as always caution is advised. Generally this hook is
used to check for potential distribution errors not caught by the
standard mechanism.
Speaking about potential distribution errors, distcheck
will also
ensure that the distclean
target actually removes all built
files. This is done by running make distcleancheck
at the end of
the VPATH
build. By default, distcleancheck
will run
distclean
and then make sure the build tree has been emptied by
running $(distcleancheck_listfiles)
. Usually this check will
find generated files that you forgot to add to the DISTCLEANFILES
variable (see section 14. What Gets Cleaned).
The distcleancheck
behaviour should be ok for most packages,
otherwise you have the possibility to override the definitition of
either the distcleancheck
target, or the
$(distcleancheck_listfiles)
variable. For instance to disable
distcleancheck
completely, add the following rule to your
top-level `Makefile.am':
distcleancheck: @: |
If you want distcleancheck
to ignore built files which have not
been cleaned because they are also part of the distribution, add the
following definition instead:
distcleancheck_listfiles = \ find -type f -exec sh -c 'test -f $(srcdir)/{} || echo {}' ';' |
The above definition is not the default because it's usually an error if your Makefiles cause some distributed files to be rebuilt when the user build the package. (Think about the user missing the tool required to build the file; or if the required tool is built by your package, consider the cross-compilation case where it can't be run.)
distcheck
also checks that the uninstall
target works
properly, both for ordinary and `DESTDIR' builds. It does this
by invoking make uninstall
, and then it checks the install tree
to see if any files are left over. This check will make sure that you
correctly coded your uninstall
-related targets.
By default, the checking is done by the distuninstallcheck
target,
and the list of files in the install tree is generated by
$(distuninstallcheck_listfiles
) (this is a variable whose value is
a shell command to run that prints the list of files to stdout).
Either of these can be overridden to modify the behavior of
distcheck
. For instance, to disable this check completely, you
would write:
distuninstallcheck: @: |
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake generates a `.tar.gz' file when asked to create a
distribution and other archives formats, 17. Changing Automake's Behavior. The target
dist-gzip
generates the `.tar.gz' file only.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake supports two forms of test suites.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
If the variable TESTS
is defined, its value is taken to be a list
of programs to run in order to do the testing. The programs can either
be derived objects or source objects; the generated rule will look both
in srcdir
and `.'. Programs needing data files should look
for them in srcdir
(which is both an environment variable and a
make variable) so they work when building in a separate directory
(see section `Build Directories' in The Autoconf Manual), and in particular for the distcheck
target
(see section 15. What Goes in a Distribution).
The number of failures will be printed at the end of the run. If a given test program exits with a status of 77, then its result is ignored in the final count. This feature allows non-portable tests to be ignored in environments where they don't make sense.
The variable TESTS_ENVIRONMENT
can be used to set environment
variables for the test run; the environment variable srcdir
is
set in the rule. If all your test programs are scripts, you can also
set TESTS_ENVIRONMENT
to an invocation of the shell (e.g.
`$(SHELL) -x'); this can be useful for debugging the tests.
You may define the variable XFAIL_TESTS
to a list of tests
(usually a subset of TESTS
) that are expected to fail. This will
reverse the result of those tests.
Automake ensures that each program listed in TESTS
is built
before any tests are run; you can list both source and derived programs
in TESTS
. For instance, you might want to run a C program as a
test. To do this you would list its name in TESTS
and also in
check_PROGRAMS
, and then specify it as you would any other
program.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
If `dejagnu' appears in
AUTOMAKE_OPTIONS
, then a dejagnu
-based test suite is
assumed. The variable DEJATOOL
is a list of names which are
passed, one at a time, as the --tool
argument to runtest
invocations; it defaults to the name of the package.
The variable RUNTESTDEFAULTFLAGS
holds the --tool
and
--srcdir
flags that are passed to dejagnu by default; this can be
overridden if necessary.
The variables EXPECT
and RUNTEST
can
also be overridden to provide project-specific values. For instance,
you will need to do this if you are testing a compiler toolchain,
because the default values do not take into account host and target
names.
The contents of the variable RUNTESTFLAGS
are passed to the
runtest
invocation. This is considered a "user variable"
(see section 2.5 Variables reserved for the user). If you need to set runtest
flags in
`Makefile.am', you can use AM_RUNTESTFLAGS
instead.
Automake will generate rules to create a local `site.exp' file,
defining various variables detected by ./configure
. This file
is automatically read by DejaGnu. It is ok for the user of a package
to edit this file in order to tune the test suite. However this is
not the place where the test suite author should define new variables:
this should be done elsewhere in the real test suite code.
Especially, `site.exp' should not be distributed.
In either case, the testing is done via `make check'.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
The installcheck
target is available to the user as a way to run
any tests after the package has been installed. You can add tests to
this by writing an installcheck-local
target.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Various features of Automake can be controlled by options in the
`Makefile.am'. Such options are applied on a per-`Makefile'
basis when listed in a special `Makefile' variable named
AUTOMAKE_OPTIONS
. They are applied globally to all processed
`Makefiles' when listed in the first argument of
AM_INIT_AUTOMAKE
in `configure.in'. Currently understood
options are:
gnits
gnu
foreign
cygnus
Set the strictness as appropriate. The gnits
option also implies
readme-alpha
and check-news
.
ansi2knr
path/ansi2knr
check-news
make dist
to fail unless the current version number appears
in the first few lines of the `NEWS' file.
dejagnu
dejagnu
-specific rules to be generated. See section 16. Support for test suites.
dist-bzip2
dist-bzip2
target, creating a bzip2 tar archive of the
distribution. dist
will create it in addition to the other
formats. bzip2 archives are frequently smaller than gzipped archives.
dist-shar
dist-shar
target, creating a shar archive of the
distribution. dist
will create it in addition to the other
formats.
dist-zip
dist-zip
target, creating a zip archive of the
distribution. dist
will create it in addition to the other
formats.
dist-tarZ
dist-tarZ
target, creating a compressed tar archive of
the distribution. dist
will create it in addition to the other
formats.
no-define
AM_INIT_AUTOMAKE
. It will prevent the PACKAGE
and
VERSION
variables to be AC_DEFINE
d.
no-dependencies
no-exeext
EXEEXT
is found to be empty. However, by default automake will
generate an error for this use. The no-exeext
option will
disable this error. This is intended for use only where it is known in
advance that the package will not be ported to Windows, or any other
operating system using extensions on executables.
no-installinfo
info
and install-info
targets will still be available. This option is disallowed at
`GNU' strictness and above.
no-installman
install-man
target will still
be available for optional installation. This option is disallowed at
`GNU' strictness and above.
nostdinc
no-texinfo.tex
readme-alpha
std-options
installcheck
target check that installed scripts and
programs support the --help
and --version
options.
This also provides a basic check that the program's
run-time dependencies are satisfied after installation.
In a few situations, programs (or scripts) have to be exempted from this
test. For instance false
(from GNU sh-utils) is never
successful, even for --help
or --version
. You can list
such programs in the variable AM_INSTALLCHECK_STD_OPTIONS_EXEMPT
.
Programs (not scripts) listed in this variable should be suffixed by
$(EXEEXT)
for the sake of Win32 or OS/2. For instance suppose we
build false
as a program but true.sh
as a script, and that
neither of them support --help
or --version
:
AUTOMAKE_OPTIONS = std-options bin_PROGRAMS = false ... bin_SCRIPTS = true.sh ... AM_INSTALLCHECK_STD_OPTIONS_EXEMPT = false$(EXEEXT) true.sh |
subdir-objects
-Wcategory
or --warnings=category
AM_INIT_AUTOMAKE([-Wall])
in your `configure.in'.
Unrecognized options are diagnosed by automake
.
If you want an option to apply to all the files in the tree, you can use
the AM_INIT_AUTOMAKE
macro in `configure.in'.
See section 5.6 Autoconf macros supplied with Automake.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
There are a few rules and variables that didn't fit anywhere else.
18.1 Interfacing to etags
Interfacing to etags and mkid 18.2 Handling new file extensions 18.3 Support for Multilibs Support for multilibbing.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
etags
Automake will generate rules to generate `TAGS' files for use with GNU Emacs under some circumstances.
If any C, C++ or Fortran 77 source code or headers are present, then
tags
and TAGS
targets will be generated for the directory.
At the topmost directory of a multi-directory package, a tags
target file will be generated which, when run, will generate a
`TAGS' file that includes by reference all `TAGS' files from
subdirectories.
The tags
target will also be generated if the variable
ETAGS_ARGS
is defined. This variable is intended for use in
directories which contain taggable source that etags
does not
understand. The user can use the ETAGSFLAGS
to pass additional
flags to etags
; AM_ETAGSFLAGS
is also available for use in
`Makefile.am'.
Here is how Automake generates tags for its source, and for nodes in its Texinfo file:
ETAGS_ARGS = automake.in --lang=none \ --regex='/^@node[ \t]+\([^,]+\)/\1/' automake.texi |
If you add filenames to `ETAGS_ARGS', you will probably also
want to set `TAGS_DEPENDENCIES'. The contents of this variable
are added directly to the dependencies for the tags
target.
Automake also generates a ctags
target which can be used to
build vi
-style `tags' files. The variable CTAGS
is the name of the program to invoke (by default `ctags');
CTAGSFLAGS
can be used by the user to pass additional flags,
and AM_CTAGSFLAGS
can be used by the `Makefile.am'.
Automake will also generate an ID
target which will run
mkid
on the source. This is only supported on a
directory-by-directory basis.
Automake also supports the GNU Global Tags program. The GTAGS
target runs Global Tags
automatically and puts the result in the top build directory. The
variable GTAGS_ARGS
holds arguments which are passed to
gtags
.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
It is sometimes useful to introduce a new implicit rule to handle a file type that Automake does not know about.
For instance, suppose you had a compiler which could compile `.foo' files to `.o' files. You would simply define an suffix rule for your language:
.foo.o: foocc -c -o $@ $< |
Then you could directly use a `.foo' file in a `_SOURCES' variable and expect the correct results:
bin_PROGRAMS = doit doit_SOURCES = doit.foo |
This was the simpler and more common case. In other cases, you will
have to help Automake to figure which extensions you are defining your
suffix rule for. This usually happens when your extensions does not
start with a dot. Then, all you have to do is to put a list of new
suffixes in the SUFFIXES
variable before you define your
implicit rule.
For instance the following definition prevents Automake to misinterpret `.idlC.cpp:' as an attempt to transform `.idlC' into `.cpp'.
SUFFIXES = .idl C.cpp .idlC.cpp: # whatever |
As you may have noted, the SUFFIXES
variable behaves like the
.SUFFIXES
special target of make
. You should not touch
.SUFFIXES
yourself, but use SUFFIXES
instead and let
Automake generate the suffix list for .SUFFIXES
. Any given
SUFFIXES
go at the start of the generated suffixes list, followed
by Automake generated suffixes not already in the list.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake has support for an obscure feature called multilibs. A multilib is a library which is built for multiple different ABIs at a single time; each time the library is built with a different target flag combination. This is only useful when the library is intended to be cross-compiled, and it is almost exclusively used for compiler support libraries.
The multilib support is still experimental. Only use it if you are familiar with multilibs and can debug problems you might encounter.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake supports an include
directive which can be used to
include other `Makefile' fragments when automake
is run.
Note that these fragments are read and interpreted by automake
,
not by make
. As with conditionals, make
has no idea that
include
is in use.
There are two forms of include
:
include $(srcdir)/file
include $(top_srcdir)/file
Note that if a fragment is included inside a conditional, then the condition applies to the entire contents of that fragment.
Makefile fragments included this way are always distributed because there are needed to rebuild `Makefile.in'.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake supports a simple type of conditionals.
Before using a conditional, you must define it by using
AM_CONDITIONAL
in the configure.in
file (see section 5.6 Autoconf macros supplied with Automake).
The shell condition (suitable for use in a shell if
statement) is evaluated when configure
is run. Note that you
must arrange for every AM_CONDITIONAL
to be invoked every
time configure
is run -- if AM_CONDITIONAL
is run
conditionally (e.g., in a shell if
statement), then the result
will confuse automake.
Conditionals typically depend upon options which the user provides to
the configure
script. Here is an example of how to write a
conditional which is true if the user uses the `--enable-debug'
option.
AC_ARG_ENABLE(debug, [ --enable-debug Turn on debugging], [case "${enableval}" in yes) debug=true ;; no) debug=false ;; *) AC_MSG_ERROR(bad value ${enableval} for --enable-debug) ;; esac],[debug=false]) AM_CONDITIONAL(DEBUG, test x$debug = xtrue) |
Here is an example of how to use that conditional in `Makefile.am':
if DEBUG DBG = debug else DBG = endif noinst_PROGRAMS = $(DBG) |
This trivial example could also be handled using EXTRA_PROGRAMS (see section 9.1.4 Conditional compilation of programs).
You may only test a single variable in an if
statement, possibly
negated using `!'. The else
statement may be omitted.
Conditionals may be nested to any depth. You may specify an argument to
else
in which case it must be the negation of the condition used
for the current if
. Similarly you may specify the condition
which is closed by an end
:
if DEBUG DBG = debug else !DEBUG DBG = endif !DEBUG |
Unbalanced conditions are errors.
Note that conditionals in Automake are not the same as conditionals in
GNU Make. Automake conditionals are checked at configure time by the
`configure' script, and affect the translation from
`Makefile.in' to `Makefile'. They are based on options passed
to `configure' and on results that `configure' has discovered
about the host system. GNU Make conditionals are checked at make
time, and are based on variables passed to the make program or defined
in the `Makefile'.
Automake conditionals will work with any make program.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
--gnu
and --gnits
The `--gnu' option (or `gnu' in the `AUTOMAKE_OPTIONS'
variable) causes automake
to check the following:
Note that this option will be extended in the future to do even more
checking; it is advisable to be familiar with the precise requirements
of the GNU standards. Also, `--gnu' can require certain
non-standard GNU programs to exist for use by various maintainer-only
targets; for instance in the future pathchk
might be required for
`make dist'.
The `--gnits' option does everything that `--gnu' does, and checks the following as well:
--help
and --version
really print a usage message and a version string,
respectively. This is the std-options
option (see section 17. Changing Automake's Behavior).
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
--cygnus
Some packages, notably GNU GCC and GNU gdb, have a build environment originally written at Cygnus Support (subsequently renamed Cygnus Solutions, and then later purchased by Red Hat). Packages with this ancestry are sometimes referred to as "Cygnus" trees.
A Cygnus tree has slightly different rules for how a `Makefile.in'
is to be constructed. Passing `--cygnus' to automake
will
cause any generated `Makefile.in' to comply with Cygnus rules.
Here are the precise effects of `--cygnus':
runtest
, expect
,
makeinfo
and texi2dvi
.
--foreign
is implied.
check
target doesn't depend on all
.
GNU maintainers are advised to use `gnu' strictness in preference to the special Cygnus mode. Some day, perhaps, the differences between Cygnus trees and GNU trees will disappear (for instance, as GCC is made more standards compliant). At that time the special Cygnus mode will be removed.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake's implicit copying semantics means that many problems can be
worked around by simply adding some make
targets and rules to
`Makefile.in'. Automake will ignore these additions.
There are some caveats to doing this. Although you can overload a target already used by Automake, it is often inadvisable, particularly in the topmost directory of a package with subdirectories. However, various useful targets have a `-local' version you can specify in your `Makefile.in'. Automake will supplement the standard target with these user-supplied targets.
The targets that support a local version are all
, info
,
dvi
, ps
, pdf
, check
, install-data
,
install-exec
, uninstall
, installdirs
,
installcheck
and the various clean
targets
(mostlyclean
, clean
, distclean
, and
maintainer-clean
). Note that there are no
uninstall-exec-local
or uninstall-data-local
targets; just
use uninstall-local
. It doesn't make sense to uninstall just
data or just executables.
For instance, here is one way to install a file in `/etc':
install-data-local: $(INSTALL_DATA) $(srcdir)/afile $(DESTDIR)/etc/afile |
Some targets also have a way to run another target, called a hook,
after their work is done. The hook is named after the principal target,
with `-hook' appended. The targets allowing hooks are
install-data
, install-exec
, uninstall
, dist
,
and distcheck
.
For instance, here is how to create a hard link to an installed program:
install-exec-hook: ln $(DESTDIR)$(bindir)/program $(DESTDIR)$(bindir)/proglink |
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Automake places no restrictions on the distribution of the resulting `Makefile.in's. We still encourage software authors to distribute their work under terms like those of the GPL, but doing so is not required to use Automake.
Some of the files that can be automatically installed via the
--add-missing
switch do fall under the GPL. However, these also
have a special exception allowing you to distribute them with your
package, regardless of the licensing you choose.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
New Automake releases usually include bug fixes and new features. Unfortunately they may also introduce new bugs and incompatibilities. This makes four reasons why a package may require a particular Automake version.
Things get worse when maintaining a large tree of packages, each one requiring a different version of Automake. In the past, this meant that any developer (and sometime users) had to install several versions of Automake in different places, and switch `$PATH' appropriately for each package.
Starting with version 1.6, Automake installs versioned binaries. This means you can install several versions of Automake in the same `$prefix', and can select an arbitrary Automake version by running `automake-1.6' or `automake-1.7' without juggling with `$PATH'. Furthermore, `Makefile''s generated by Automake 1.6 will use `automake-1.6' explicitly in their rebuild rules.
Note that `1.6' in `automake-1.6' is Automake's API version, not Automake's version. If a bug fix release is made, for instance Automake 1.6.1, the API version will remain 1.6. This means that a package which work with Automake 1.6 should also work with 1.6.1; after all, this is what people expect from bug fix releases.
Note that if your package relies on a feature or a bug fix introduced in a release, you can pass this version as an option to Automake to ensure older releases will not be used. For instance, use this in your `configure.in':
AM_INIT_AUTOMAKE(1.6.1) dnl Require Automake 1.6.1 or better. |
AUTOMAKE_OPTIONS = 1.6.1 # Require Automake 1.6.1 or better. |
Automake's programming interface is not easy to define. Basically it should include at least all documented variables and targets that a `Makefile.am' author can use, any behavior associated with them (e.g. the places where `-hook''s are run), the command line interface of `automake' and `aclocal', ...
Every undocumented variable, target, or command line option, is not part of the API. You should avoid using them, as they could change from one version to the other (even in bug fix releases, if this helps to fix a bug).
If it turns out you need to use such a undocumented feature, contact [email protected] and try to get it documented and exercised by the test-suite.
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Jump to: | _
A B C D E F G H I J L M N O P R S T V W X Y |
---|
Jump to: | _
A B C D E F G H I J L M N O P R S T V W X Y |
---|
[ < ] | [ > ] | [ << ] | [ Up ] | [ >> ] | [Top] | [Contents] | [Index] | [ ? ] |
Jump to: | #
-
@
_
A B C D E F G H I J L M N O P R S T U V W Y Z |
---|
Jump to: | #
-
@
_
A B C D E F G H I J L M N O P R S T U V W Y Z |
---|
[Top] | [Contents] | [Index] | [ ? ] |
These variables are also called make macros in Make terminology, however in this manual we reserve the term macro for Autoconf's macros.
Autoconf 2.50 promotes `configure.ac' over `configure.in'. The rest of this documentation will refer to `configure.in' as this use is not yet spread, but Automake supports `configure.ac' too.
Don't try seeking a solution where `opt/Makefile' is created conditionally, this is a lot trickier than the solutions presented here.
We believe. This work is new and there are probably warts. See section 1. Introduction, for information on reporting bugs.
There are other, more obscure reasons reasons for this limitation as well.
Much, if not most, of the information in the following sections pertaining to preprocessing Fortran 77 programs was taken almost verbatim from section `Catalogue of Rules' in The GNU Make Manual.
For example,
the cfortran package
addresses all of these inter-language issues, and runs under nearly all
Fortran 77, C and C++ compilers on nearly all platforms. However,
cfortran
is not yet Free Software, but it will be in the next
major release.
See http://sources.redhat.com/automake/dependencies.html for more information on the history and experiences with automatic dependency tracking in Automake
However, for the case of a
non-installed header file that is actually used by a particular program,
we recommend listing it in the program's `_SOURCES' variable
instead of in noinst_HEADERS
. We believe this is more clear.
[Top] | [Contents] | [Index] | [ ? ] |
1. Introduction
2. General ideas
2.1 General Operation3. Some example packages
2.2 Strictness
2.3 The Uniform Naming Scheme
2.4 How derived variables are named
2.5 Variables reserved for the user
2.6 Programs automake might require
3.1 A simple example, start to finish4. Creating a `Makefile.in'
3.2 A classic program
3.3 Building true and false
5. Scanning `configure.in'
5.1 Configuration requirements6. The top-level `Makefile.am'
5.2 Other things Automake recognizes
5.3 Auto-generating aclocal.m4
5.4 aclocal options
5.5 Macro search path
5.5.1 Modifying the macro search path:5.6 Autoconf macros supplied with Automake--acdir
5.5.2 Modifying the macro search path:-I dir
5.5.3 Modifying the macro search path: `dirlist'
5.6.1 Public macros5.7 Writing your own aclocal macros
5.6.2 Private macros
6.1 Recursing subdirectories7. An Alternative Approach to Subdirectories
6.2 Conditional subdirectories
6.2.1 Conditional subdirectories withAM_CONDITIONAL
6.2.2 Conditional subdirectories withAC_SUBST
6.2.3 HowDIST_SUBDIRS
is used
8. Rebuilding Makefiles
9. Building Programs and Libraries
9.1 Building a program10. Other Derived Objects
9.1.1 Defining program sources9.2 Building a library
9.1.2 Linking the program
9.1.3 Conditional compilation of sources
9.1.3.1 Conditional compilation using9.1.4 Conditional compilation of programs_LDADD
substitutions
9.1.3.2 Conditional compilation using Automake conditionals
9.3 Building a Shared Library
9.4 Program and Library Variables
9.5 Special handling for LIBOBJS and ALLOCA
9.6 Variables used when building a program
9.7 Yacc and Lex support
9.8 C++ Support
9.9 Assembly Support
9.10 Fortran 77 Support
9.10.1 Preprocessing Fortran 779.11 Java Support
9.10.2 Compiling Fortran 77 Files
9.10.3 Mixing Fortran 77 With C and C++
9.10.3.1 How the Linker is Chosen9.10.4 Fortran 77 and Autoconf
9.12 Support for Other Languages
9.13 Automatic de-ANSI-fication
9.14 Automatic dependency tracking
9.15 Support for executable extensions
10.1 Executable Scripts11. Other GNU Tools
10.2 Header files
10.3 Architecture-independent data files
10.4 Built sources
10.4.1 Built sources example
First try
UsingBUILT_SOURCES
Recording dependencies manually
Build `bindir.h' from `configure'
Build `bindir.c', not `bindir.h'.
Which is best?
11.1 Emacs Lisp12. Building documentation
11.2 Gettext
11.3 Libtool
11.4 Java
11.5 Python
12.1 Texinfo13. What Gets Installed
12.2 Man pages
13.1 Basics of installation14. What Gets Cleaned
13.2 The two parts of install
13.3 Extending installation
13.4 Staged installs
13.5 Rules for the user
15. What Goes in a Distribution
15.1 Basics of distribution16. Support for test suites
15.2 Fine-grained distribution control
15.3 The dist hook
15.4 Checking the distribution
15.5 The types of distributions
16.1 Simple Tests17. Changing Automake's Behavior
16.2 DejaGNU Tests
16.3 Install Tests
18. Miscellaneous Rules
18.1 Interfacing to19. Includeetags
18.2 Handling new file extensions
18.3 Support for Multilibs
20. Conditionals
21. The effect of--gnu
and--gnits
22. The effect of--cygnus
23. When Automake Isn't Enough
24. Distributing `Makefile.in's
25. Automake API versioning
Macro and Variable Index
General Index
[Top] | [Contents] | [Index] | [ ? ] |
1. Introduction
2. General ideas
3. Some example packages
4. Creating a `Makefile.in'
5. Scanning `configure.in'
6. The top-level `Makefile.am'
7. An Alternative Approach to Subdirectories
8. Rebuilding Makefiles
9. Building Programs and Libraries
10. Other Derived Objects
11. Other GNU Tools
12. Building documentation
13. What Gets Installed
14. What Gets Cleaned
15. What Goes in a Distribution
16. Support for test suites
17. Changing Automake's Behavior
18. Miscellaneous Rules
19. Include
20. Conditionals
21. The effect of--gnu
and--gnits
22. The effect of--cygnus
23. When Automake Isn't Enough
24. Distributing `Makefile.in's
25. Automake API versioning
Macro and Variable Index
General Index
[Top] | [Contents] | [Index] | [ ? ] |
Button | Name | Go to | From 1.2.3 go to |
---|---|---|---|
[ < ] | Back | previous section in reading order | 1.2.2 |
[ > ] | Forward | next section in reading order | 1.2.4 |
[ << ] | FastBack | previous or up-and-previous section | 1.1 |
[ Up ] | Up | up section | 1.2 |
[ >> ] | FastForward | next or up-and-next section | 1.3 |
[Top] | Top | cover (top) of document | |
[Contents] | Contents | table of contents | |
[Index] | Index | concept index | |
[ ? ] | About | this page |