1# ===========================================================================
2#         http://www.gnu.org/software/autoconf-archive/ax_lapack.html
3# ===========================================================================
4#
5# SYNOPSIS
6#
7#   AX_LAPACK([ACTION-IF-FOUND[, ACTION-IF-NOT-FOUND]])
8#
9# DESCRIPTION
10#
11#   This macro looks for a library that implements the LAPACK linear-algebra
12#   interface (see http://www.netlib.org/lapack/). On success, it sets the
13#   LAPACK_LIBS output variable to hold the requisite library linkages.
14#
15#   To link with LAPACK, you should link with:
16#
17#     $LAPACK_LIBS $BLAS_LIBS $LIBS $FLIBS
18#
19#   in that order. BLAS_LIBS is the output variable of the AX_BLAS macro,
20#   called automatically. FLIBS is the output variable of the
21#   AC_F77_LIBRARY_LDFLAGS macro (called if necessary by AX_BLAS), and is
22#   sometimes necessary in order to link with F77 libraries. Users will also
23#   need to use AC_F77_DUMMY_MAIN (see the autoconf manual), for the same
24#   reason.
25#
26#   The user may also use --with-lapack=<lib> in order to use some specific
27#   LAPACK library <lib>. In order to link successfully, however, be aware
28#   that you will probably need to use the same Fortran compiler (which can
29#   be set via the F77 env. var.) as was used to compile the LAPACK and BLAS
30#   libraries.
31#
32#   ACTION-IF-FOUND is a list of shell commands to run if a LAPACK library
33#   is found, and ACTION-IF-NOT-FOUND is a list of commands to run it if it
34#   is not found. If ACTION-IF-FOUND is not specified, the default action
35#   will define HAVE_LAPACK.
36#
37# LICENSE
38#
39#   Copyright (c) 2009 Steven G. Johnson <stevenj@alum.mit.edu>
40#
41#   This program is free software: you can redistribute it and/or modify it
42#   under the terms of the GNU General Public License as published by the
43#   Free Software Foundation, either version 3 of the License, or (at your
44#   option) any later version.
45#
46#   This program is distributed in the hope that it will be useful, but
47#   WITHOUT ANY WARRANTY; without even the implied warranty of
48#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
49#   Public License for more details.
50#
51#   You should have received a copy of the GNU General Public License along
52#   with this program. If not, see <http://www.gnu.org/licenses/>.
53#
54#   As a special exception, the respective Autoconf Macro's copyright owner
55#   gives unlimited permission to copy, distribute and modify the configure
56#   scripts that are the output of Autoconf when processing the Macro. You
57#   need not follow the terms of the GNU General Public License when using
58#   or distributing such scripts, even though portions of the text of the
59#   Macro appear in them. The GNU General Public License (GPL) does govern
60#   all other use of the material that constitutes the Autoconf Macro.
61#
62#   This special exception to the GPL applies to versions of the Autoconf
63#   Macro released by the Autoconf Archive. When you make and distribute a
64#   modified version of the Autoconf Macro, you may extend this special
65#   exception to the GPL to apply to your modified version as well.
66
67#serial 7
68
69AU_ALIAS([ACX_LAPACK], [AX_LAPACK])
70AC_DEFUN([AX_LAPACK], [
71AC_REQUIRE([AX_BLAS])
72ax_lapack_ok=no
73
74AC_ARG_WITH(lapack,
75        [AS_HELP_STRING([--with-lapack=<lib>], [use LAPACK library <lib>])])
76case $with_lapack in
77        yes | "") ;;
78        no) ax_lapack_ok=disable ;;
79        -* | */* | *.a | *.so | *.so.* | *.o) LAPACK_LIBS="$with_lapack" ;;
80        *) LAPACK_LIBS="-l$with_lapack" ;;
81esac
82
83# Get fortran linker name of LAPACK function to check for.
84AC_F77_FUNC(cheev)
85
86# We cannot use LAPACK if BLAS is not found
87if test "x$ax_blas_ok" != xyes; then
88        ax_lapack_ok=noblas
89        LAPACK_LIBS=""
90fi
91
92# First, check LAPACK_LIBS environment variable
93if test "x$LAPACK_LIBS" != x; then
94        save_LIBS="$LIBS"; LIBS="$LAPACK_LIBS $BLAS_LIBS $LIBS $FLIBS"
95        AC_MSG_CHECKING([for $cheev in $LAPACK_LIBS])
96        AC_TRY_LINK_FUNC($cheev, [ax_lapack_ok=yes], [LAPACK_LIBS=""])
97        AC_MSG_RESULT($ax_lapack_ok)
98        LIBS="$save_LIBS"
99        if test $ax_lapack_ok = no; then
100                LAPACK_LIBS=""
101        fi
102fi
103
104# LAPACK linked to by default?  (is sometimes included in BLAS lib)
105if test $ax_lapack_ok = no; then
106        save_LIBS="$LIBS"; LIBS="$LIBS $BLAS_LIBS $FLIBS"
107        AC_CHECK_FUNC($cheev, [ax_lapack_ok=yes])
108        LIBS="$save_LIBS"
109fi
110
111# Generic LAPACK library?
112for lapack in lapack lapack_rs6k; do
113        if test $ax_lapack_ok = no; then
114                save_LIBS="$LIBS"; LIBS="$BLAS_LIBS $LIBS"
115                AC_CHECK_LIB($lapack, $cheev,
116                    [ax_lapack_ok=yes; LAPACK_LIBS="-l$lapack"], [], [$FLIBS])
117                LIBS="$save_LIBS"
118        fi
119done
120
121AC_SUBST(LAPACK_LIBS)
122
123# Finally, execute ACTION-IF-FOUND/ACTION-IF-NOT-FOUND:
124if test x"$ax_lapack_ok" = xyes; then
125        ifelse([$1],,AC_DEFINE(HAVE_LAPACK,1,[Define if you have LAPACK library.]),[$1])
126        :
127else
128        ax_lapack_ok=no
129        $2
130fi
131])dnl AX_LAPACK
132