--- a/acx_lapack.m4
+++ b/acx_lapack.m4
@@ -1,41 +1,79 @@
-dnl @synopsis ACX_LAPACK([ACTION-IF-FOUND[, ACTION-IF-NOT-FOUND]])
-dnl
-dnl This macro looks for a library that implements the LAPACK
-dnl linear-algebra interface (see http://www.netlib.org/lapack/).
-dnl On success, it sets the LAPACK_LIBS output variable to
-dnl hold the requisite library linkages.
-dnl
-dnl To link with LAPACK, you should link with:
-dnl
-dnl     $LAPACK_LIBS $BLAS_LIBS $LIBS $FLIBS
-dnl
-dnl in that order.  BLAS_LIBS is the output variable of the ACX_BLAS
-dnl macro, called automatically.  FLIBS is the output variable of the
-dnl AC_F77_LIBRARY_LDFLAGS macro (called if necessary by ACX_BLAS),
-dnl and is sometimes necessary in order to link with F77 libraries.
-dnl Users will also need to use AC_F77_DUMMY_MAIN (see the autoconf
-dnl manual), for the same reason.
-dnl
-dnl The user may also use --with-lapack=<lib> in order to use some
-dnl specific LAPACK library <lib>.  In order to link successfully,
-dnl however, be aware that you will probably need to use the same
-dnl Fortran compiler (which can be set via the F77 env. var.) as
-dnl was used to compile the LAPACK and BLAS libraries.
-dnl
-dnl ACTION-IF-FOUND is a list of shell commands to run if a LAPACK
-dnl library is found, and ACTION-IF-NOT-FOUND is a list of commands
-dnl to run it if it is not found.  If ACTION-IF-FOUND is not specified,
-dnl the default action will define HAVE_LAPACK.
-dnl
-dnl @version $Id: acx_lapack.m4,v 1.3 2002/03/12 09:12:44 simons Exp $
-dnl @author Steven G. Johnson <stevenj@alum.mit.edu>
+# ===========================================================================
+#               http://autoconf-archive.cryp.to/acx_lapack.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   ACX_LAPACK([ACTION-IF-FOUND[, ACTION-IF-NOT-FOUND]])
+#
+# DESCRIPTION
+#
+#   This macro looks for a library that implements the LAPACK linear-algebra
+#   interface (see http://www.netlib.org/lapack/). On success, it sets the
+#   LAPACK_LIBS output variable to hold the requisite library linkages.
+#
+#   To link with LAPACK, you should link with:
+#
+#       $LAPACK_LIBS $BLAS_LIBS $LIBS $FLIBS
+#
+#   in that order. BLAS_LIBS is the output variable of the ACX_BLAS macro,
+#   called automatically. FLIBS is the output variable of the
+#   AC_F77_LIBRARY_LDFLAGS macro (called if necessary by ACX_BLAS), and is
+#   sometimes necessary in order to link with F77 libraries. Users will also
+#   need to use AC_F77_DUMMY_MAIN (see the autoconf manual), for the same
+#   reason.
+#
+#   The user may also use --with-lapack=<lib> in order to use some specific
+#   LAPACK library <lib>. In order to link successfully, however, be aware
+#   that you will probably need to use the same Fortran compiler (which can
+#   be set via the F77 env. var.) as was used to compile the LAPACK and BLAS
+#   libraries.
+#
+#   ACTION-IF-FOUND is a list of shell commands to run if a LAPACK library
+#   is found, and ACTION-IF-NOT-FOUND is a list of commands to run it if it
+#   is not found. If ACTION-IF-FOUND is not specified, the default action
+#   will define HAVE_LAPACK.
+#
+# LAST MODIFICATION
+#
+#   2008-06-29
+#
+# COPYLEFT
+#
+#   Copyright (c) 2008 Steven G. Johnson <stevenj@alum.mit.edu>
+#
+#   This program is free software: you can redistribute it and/or modify it
+#   under the terms of the GNU General Public License as published by the
+#   Free Software Foundation, either version 3 of the License, or (at your
+#   option) any later version.
+#
+#   This program is distributed in the hope that it will be useful, but
+#   WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
+#   Public License for more details.
+#
+#   You should have received a copy of the GNU General Public License along
+#   with this program. If not, see <http://www.gnu.org/licenses/>.
+#
+#   As a special exception, the respective Autoconf Macro's copyright owner
+#   gives unlimited permission to copy, distribute and modify the configure
+#   scripts that are the output of Autoconf when processing the Macro. You
+#   need not follow the terms of the GNU General Public License when using
+#   or distributing such scripts, even though portions of the text of the
+#   Macro appear in them. The GNU General Public License (GPL) does govern
+#   all other use of the material that constitutes the Autoconf Macro.
+#
+#   This special exception to the GPL applies to versions of the Autoconf
+#   Macro released by the Autoconf Macro Archive. When you make and
+#   distribute a modified version of the Autoconf Macro, you may extend this
+#   special exception to the GPL to apply to your modified version as well.
 
 AC_DEFUN([ACX_LAPACK], [
 AC_REQUIRE([ACX_BLAS])
 acx_lapack_ok=no
 
 AC_ARG_WITH(lapack,
-        [AS_HELP_STRING([--with-lapack=<lib>], [use LAPACK library <lib>])])
+        [AC_HELP_STRING([--with-lapack=<lib>], [use LAPACK library <lib>])])
 case $with_lapack in
         yes | "") ;;
         no) acx_lapack_ok=disable ;;
@@ -44,26 +82,22 @@
 esac
 
 # Get fortran linker name of LAPACK function to check for.
-if $have_fortran_compiler; then
-  AC_F77_FUNC(cheev)
-elif $have_f2c; then
-  cheev=cheev_
-fi
+AC_F77_FUNC(cheev)
 
 # We cannot use LAPACK if BLAS is not found
 if test "x$acx_blas_ok" != xyes; then
         acx_lapack_ok=noblas
+        LAPACK_LIBS=""
 fi
 
 # First, check LAPACK_LIBS environment variable
 if test "x$LAPACK_LIBS" != x; then
         save_LIBS="$LIBS"; LIBS="$LAPACK_LIBS $BLAS_LIBS $LIBS $FLIBS"
         AC_MSG_CHECKING([for $cheev in $LAPACK_LIBS])
-        AC_LINK_IFELSE([AC_LANG_CALL([], [$cheev])],
-		       [acx_lapack_ok=yes], [LAPACK_LIBS=""])
+        AC_TRY_LINK_FUNC($cheev, [acx_lapack_ok=yes], [LAPACK_LIBS=""])
         AC_MSG_RESULT($acx_lapack_ok)
         LIBS="$save_LIBS"
-        if test acx_lapack_ok = no; then
+        if test $acx_lapack_ok = no; then
                 LAPACK_LIBS=""
         fi
 fi