path: root/pkgs/by-name/se/sextractor/0001-fix-openblas-check.patch

From 04016a19c79bb72962c3d09f31bf22159671a159 Mon Sep 17 00:00:00 2001
From: mathar <mathar@mpia-hd.mpg.de>
Date: Mon, 21 Jul 2025 15:26:09 +0200
Subject: [PATCH] separate m4 macros checking openblas and lapacke

---
 configure.ac       |  34 +++----
 m4/acx_atlas.m4    |   2 +-
 m4/acx_openblas.m4 | 140 -------------------------
 m4/ax_blas.m4      | 248 +++++++++++++++++++++++++++++++++++++++++++++
 m4/ax_lapack.m4    | 122 ++++++++++++++++++++++
 5 files changed, 385 insertions(+), 161 deletions(-)
 delete mode 100644 m4/acx_openblas.m4
 create mode 100644 m4/ax_blas.m4
 create mode 100644 m4/ax_lapack.m4

diff --git a/configure.ac b/configure.ac
index 0b2e7ae7..d2edddea 100644
--- a/configure.ac
+++ b/configure.ac
@@ -26,7 +26,7 @@
 #	You should have received a copy of the GNU General Public License
 #	along with SExtractor. If not, see <http://www.gnu.org/licenses/>.
 #
-#	Last modified:		27/03/2025
+#	Last modified:		2025-07-21
 #
 #%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
@@ -53,16 +53,6 @@ AC_SUBST(DATE2, "$date2")
 AC_SUBST(DATE3, "$date3")
 AM_CFLAGS="$AM_CFLAGS -Wall"
 
-# Include macros
-sinclude(acx_atlas.m4)
-sinclude(acx_openblas.m4)
-sinclude(acx_fftw.m4)
-sinclude(acx_mkl.m4)
-sinclude(acx_cfitsio.m4)
-sinclude(acx_prog_cc_optim.m4)
-sinclude(acx_pthread.m4)
-sinclude(acx_urbi_resolve_dir.m4)
-
 # Provide a special option for setting the package release number
 AC_ARG_WITH(release,
 	[AS_HELP_STRING([--with-release=<release number>],
@@ -310,23 +300,27 @@ if test "$enable_model_fitting" != "no"; then
 
     if test "x$enable_openblas" = "xyes"; then
 ######## Handle the OpenBLAS library (linear algebra: BLAS + LAPACKe) ########
-      ACX_OPENBLAS($with_openblas_libdir, $with_openblas_incdir, $use_pthreads, no,
+      AC_MSG_NOTICE("checking openblas + lapacke")
+      AX_BLAS(
+        [
+          LIBS="$BLAS_LIBS $LIBS"
+        ],
+        AC_MSG_ERROR([blas error... Exiting.])
+      )
+      AX_LAPACK($with_openblas_libdir, $with_openblas_incdir,
         [
-          AM_CFLAGS="$AM_CFLAGS $OPENBLAS_CFLAGS "
-          AM_LDFLAGS="$AM_LDFLAGS $OPENBLAS_LDFLAGS "
-          LIBS="$OPENBLAS_LIBS $LIBS"
-          if test "$OPENBLAS_WARN" != ""; then
-            AC_MSG_WARN([$OPENBLAS_WARN])
-          fi
+          AM_CFLAGS="$AM_CFLAGS $LAPACK_CFLAGS "
+          AM_LDFLAGS="$AM_LDFLAGS $LAPACK_LDFLAGS "
+          LIBS="$LAPACK_LIBS $LIBS"
         ],
-        AC_MSG_ERROR([$OPENBLAS_ERROR Exiting.])
+        AC_MSG_ERROR([$LAPACK_ERROR Exiting.])
       )
     else
 ######### handle the ATLAS library (linear algebra: BLAS + cLAPACK) ##########
       ACX_ATLAS($with_atlas_libdir, $with_atlas_incdir, $use_pthreads,
         [
           [LIBS="$ATLAS_LIBS $LIBS"]
-          if test "$ATLAS_WARN" != ""; then
+          if test -n $ATLAS_WARN ; then
             AC_MSG_WARN([$ATLAS_WARN])
 	  fi
         ],
diff --git a/m4/acx_atlas.m4 b/m4/acx_atlas.m4
index 6959fdb2..ddaeff7b 100644
--- a/m4/acx_atlas.m4
+++ b/m4/acx_atlas.m4
@@ -67,7 +67,7 @@ if test x$2 = x; then
   )
 fi
 
-if test x$ATLAS_ERROR = x; then
+if test "x$ATLAS_ERROR" = "x"; then
   AC_DEFINE_UNQUOTED(ATLAS_BLAS_H, "${acx_atlas_incdir}cblas.h", [BLAS header filename.])
   AC_DEFINE_UNQUOTED(ATLAS_LAPACK_H, "${acx_atlas_incdir}clapack.h", [CLAPACK header filename.])
 
diff --git a/m4/acx_openblas.m4 b/m4/acx_openblas.m4
deleted file mode 100644
index 5421eece..00000000
--- a/m4/acx_openblas.m4
+++ /dev/null
@@ -1,140 +0,0 @@
-dnl
-dnl				acx_openblas.m4
-dnl
-dnl Figure out if the OpenBLAS library and header files are installed.
-dnl
-dnl %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-dnl
-dnl	This file part of:	AstrOmatic software
-dnl
-dnl	Copyright:		(C) 2016 IAP/CNRS/UPMC
-dnl
-dnl	License:		GNU General Public License
-dnl
-dnl	AstrOmatic software is free software: you can redistribute it and/or
-dnl	modify it under the terms of the GNU General Public License as
-dnl	published by the Free Software Foundation, either version 3 of the
-dnl	License, or (at your option) any later version.
-dnl	AstrOmatic software is distributed in the hope that it will be useful,
-dnl	but WITHOUT ANY WARRANTY; without even the implied warranty of
-dnl	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-dnl	GNU General Public License for more details.
-dnl	You should have received a copy of the GNU General Public License
-dnl	along with AstrOmatic software.
-dnl	If not, see <http://www.gnu.org/licenses/>.
-dnl
-dnl	Last modified:		12/10/2016
-dnl
-dnl %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-dnl
-dnl @synopsis ACX_OPENBLAS([OPENBLAS_LIBSDIR, OPENBLAS_INCDIR, OPENBLAS_PFLAG,
-dnl                  ILP64_FLAG, [ACTION-IF-FOUND[, ACTION-IF-NOT-FOUND]]])
-dnl
-dnl You may wish to use these variables in your default LIBS:
-dnl
-dnl        LIBS="$OPENBLAS_LIBS $LIBS"
-dnl
-dnl ACTION-IF-FOUND is a list of shell commands to run if OPENBLAS
-dnl is found (HAVE_OPENBLAS is defined first), and ACTION-IF-NOT-FOUND
-dnl is a list of commands to run it if it is not found.
-
-AC_DEFUN([ACX_OPENBLAS], [
-AC_REQUIRE([AC_CANONICAL_HOST])
-
-dnl --------------------
-dnl Search include files
-dnl --------------------
-
-OPENBLAS_ERROR=""
-if test x$2 = x; then
-  [acx_openblas_incdir="openblas/"]
-  AC_CHECK_HEADERS(
-    [${acx_openblas_incdir}cblas.h ${acx_openblas_incdir}lapacke.h],,
-    [
-      [acx_openblas_incdir=""]
-      AC_CHECK_HEADER(
-        [cblas.h lapacke.h],,
-        [OPENBLAS_ERROR="OpenBLAS header files not found!"]
-      )
-    ]
-  )
-else
-  acx_openblas_incdir="$2/"
-  AC_CHECK_HEADER(
-    [${acx_openblas_incdir}cblas.h],,
-    [
-      [acx_openblas_incdir="$2/include/"]
-      AC_CHECK_HEADERS(
-        [${acx_openblas_incdir}cblas.h ${acx_openblas_incdir}lapacke.h],,
-        [OPENBLAS_ERROR="OpenBLAS header files not found in "$2"!"]
-    )]
-  )
-fi
-
-if test "x$OPENBLAS_ERROR" = "x"; then
-  AC_DEFINE_UNQUOTED(BLAS_H, "${acx_openblas_incdir}cblas.h", [BLAS header filename.])
-  AC_DEFINE_UNQUOTED(LAPACKE_H, "${acx_openblas_incdir}lapacke.h", [LAPACKe header filename.])
-
-dnl ----------------------------
-dnl Search OpenBLAS library file
-dnl ----------------------------
-
-  OLIBS="$LIBS"
-  LIBS=""
-  if test x$4 = xyes; then
-    acx_openblas_suffix="64"
-    OPENBLAS_CFLAGS="-DOPENBLAS_USE64BITINT -DLAPACK_ILP64"
-  else
-    acx_openblas_suffix=""
-    OPENBLAS_CFLAGS=""
-  fi
-  if test x$1 = x; then
-    acx_openblas_libopt=""
-  else
-    acx_openblas_libopt="-L$1"
-  fi
-  if test x$3 == xyes; then
-    AC_SEARCH_LIBS(
-      [LAPACKE_dpotrf], ["openblasp"$acx_openblas_suffix],
-      AC_DEFINE(HAVE_OPENBLASP,1,
-		[Define if you have the OpenBLAS parallel library and header files.]),
-      unset ac_cv_search_LAPACKE_dpotrf
-      [AC_SEARCH_LIBS(
-        [LAPACKE_dpotrf], ["openblas"$acx_openblas_suffix],
-	[OPENBLAS_WARN="parallel OpenBLAS"$acx_openblas_suffix" not found, reverting to scalar OpenBLAS"$acx_openblas_suffix"!"],
-        [OPENBLAS_ERROR="OpenBLAS"$acx_openblas_suffix" library file not found!"],
-        $acx_openblas_libopt
-      )],
-      $acx_openblas_libopt
-    )
-  else
-    AC_SEARCH_LIBS(
-      [LAPACKE_dpotrf], ["openblas"$acx_openblas_suffix],,
-      [OPENBLAS_ERROR="OpenBLAS"$acx_openblas_suffix" library file not found!"],
-      $acx_openblas_libopt
-    )
-  fi
-  LIBS="$OLIBS"
-fi
-
-dnl -------------------------------------------------------------------------
-dnl Finally execute ACTION-IF-FOUND/ACTION-IF-NOT-FOUND
-dnl -------------------------------------------------------------------------
-
-if test "x$OPENBLAS_ERROR" = "x"; then
-  AC_DEFINE(HAVE_OPENBLAS,1, [Define if you have the OpenBLAS library and header files.])
-  AC_DEFINE(HAVE_BLAS,1, [Define if you have the BLAS library and header files.])
-  AC_DEFINE(HAVE_LAPACKE,1, [Define if you have the LAPACKe library and header files.])
-  OPENBLAS_LIBS="$acx_openblas_libopt $ac_cv_search_LAPACKE_dpotrf"
-  AC_SUBST(OPENBLAS_CFLAGS)
-  AC_SUBST(OPENBLAS_LDFLAGS, "")
-  AC_SUBST(OPENBLAS_LIBS)
-  AC_SUBST(OPENBLAS_WARN)
-  $5
-else
-  AC_SUBST(OPENBLAS_ERROR)
-  $6
-fi
-
-])dnl ACX_OPENBLAS
-
diff --git a/m4/ax_blas.m4 b/m4/ax_blas.m4
new file mode 100644
index 00000000..851a2571
--- /dev/null
+++ b/m4/ax_blas.m4
@@ -0,0 +1,248 @@
+# ===========================================================================
+#         https://www.gnu.org/software/autoconf-archive/ax_blas.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_BLAS([ACTION-IF-FOUND[, ACTION-IF-NOT-FOUND]])
+#
+# DESCRIPTION
+#
+#   This macro looks for a library that implements the BLAS linear-algebra
+#   interface (see http://www.netlib.org/blas/). On success, it sets the
+#   BLAS_LIBS output variable to hold the requisite library linkages.
+#
+#   To link with BLAS, you should link with:
+#
+#     $BLAS_LIBS $LIBS $FLIBS
+#
+#   in that order. FLIBS is the output variable of the
+#   AC_F77_LIBRARY_LDFLAGS macro (called if necessary by AX_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.
+#
+#   Many libraries are searched for, from ATLAS to CXML to ESSL. The user
+#   may also use --with-blas=<lib> in order to use some specific BLAS
+#   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 BLAS library.
+#
+#   ACTION-IF-FOUND is a list of shell commands to run if a BLAS 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_BLAS.
+#
+# LICENSE
+#
+#   Copyright (c) 2008 Steven G. Johnson <stevenj@alum.mit.edu>
+#   Copyright (c) 2019 Geoffrey M. Oxberry <goxberry@gmail.com>
+#
+#   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 <https://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 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.
+
+#serial 21
+
+AU_ALIAS([ACX_BLAS], [AX_BLAS])
+AC_DEFUN([AX_BLAS], [
+AC_PREREQ([2.55])
+AC_REQUIRE([AC_F77_LIBRARY_LDFLAGS])
+AC_REQUIRE([AC_CANONICAL_HOST])
+ax_blas_ok=no
+
+AC_ARG_WITH(blas,
+	[AS_HELP_STRING([--with-blas=<lib>], [use BLAS library <lib>])])
+case $with_blas in
+	yes | "") ;;
+	no) ax_blas_ok=disable ;;
+	-* | */* | *.a | *.so | *.so.* | *.dylib | *.dylib.* | *.o)
+		BLAS_LIBS="$with_blas"
+	;;
+	*) BLAS_LIBS="-l$with_blas" ;;
+esac
+
+# Get fortran linker names of BLAS functions to check for.
+AC_F77_FUNC(sgemm)
+AC_F77_FUNC(dgemm)
+
+ax_blas_save_LIBS="$LIBS"
+LIBS="$LIBS $FLIBS"
+
+# First, check BLAS_LIBS environment variable
+if test $ax_blas_ok = no; then
+if test "x$BLAS_LIBS" != x; then
+	save_LIBS="$LIBS"; LIBS="$BLAS_LIBS $LIBS"
+	AC_MSG_CHECKING([for $sgemm in $BLAS_LIBS])
+	AC_LINK_IFELSE([AC_LANG_CALL([], [$sgemm])], [ax_blas_ok=yes], [BLAS_LIBS=""])
+	AC_MSG_RESULT($ax_blas_ok)
+	LIBS="$save_LIBS"
+fi
+fi
+
+# BLAS linked to by default?  (happens on some supercomputers)
+if test $ax_blas_ok = no; then
+	save_LIBS="$LIBS"; LIBS="$LIBS"
+	AC_MSG_CHECKING([if $sgemm is being linked in already])
+	AC_LINK_IFELSE([AC_LANG_CALL([], [$sgemm])], [ax_blas_ok=yes])
+	AC_MSG_RESULT($ax_blas_ok)
+	LIBS="$save_LIBS"
+fi
+
+# BLAS linked to by flexiblas? (Default on FC33+ and RHEL9+)
+
+if test $ax_blas_ok = no; then
+	AC_CHECK_LIB(flexiblas, $sgemm, [ax_blas_ok=yes
+			                BLAS_LIBS="-lflexiblas"])
+fi
+
+# BLAS in OpenBLAS library? (http://xianyi.github.com/OpenBLAS/)
+if test $ax_blas_ok = no; then
+	AC_CHECK_LIB(openblas, $sgemm, [ax_blas_ok=yes
+			                BLAS_LIBS="-lopenblas"])
+fi
+
+# BLAS in ATLAS library? (http://math-atlas.sourceforge.net/)
+if test $ax_blas_ok = no; then
+	AC_CHECK_LIB(atlas, ATL_xerbla,
+		[AC_CHECK_LIB(f77blas, $sgemm,
+		[AC_CHECK_LIB(cblas, cblas_dgemm,
+			[ax_blas_ok=yes
+			 BLAS_LIBS="-lcblas -lf77blas -latlas"],
+			[], [-lf77blas -latlas])],
+			[], [-latlas])])
+fi
+
+# BLAS in PhiPACK libraries? (requires generic BLAS lib, too)
+if test $ax_blas_ok = no; then
+	AC_CHECK_LIB(blas, $sgemm,
+		[AC_CHECK_LIB(dgemm, $dgemm,
+		[AC_CHECK_LIB(sgemm, $sgemm,
+			[ax_blas_ok=yes; BLAS_LIBS="-lsgemm -ldgemm -lblas"],
+			[], [-lblas])],
+			[], [-lblas])])
+fi
+
+# BLAS in Intel MKL library?
+if test $ax_blas_ok = no; then
+	# MKL for gfortran
+	if test x"$ac_cv_fc_compiler_gnu" = xyes; then
+		# 64 bit
+		if test $host_cpu = x86_64; then
+			AC_CHECK_LIB(mkl_gf_lp64, $sgemm,
+			[ax_blas_ok=yes;BLAS_LIBS="-lmkl_gf_lp64 -lmkl_sequential -lmkl_core -lpthread"],,
+			[-lmkl_gf_lp64 -lmkl_sequential -lmkl_core -lpthread])
+		# 32 bit
+		elif test $host_cpu = i686; then
+			AC_CHECK_LIB(mkl_gf, $sgemm,
+				[ax_blas_ok=yes;BLAS_LIBS="-lmkl_gf -lmkl_sequential -lmkl_core -lpthread"],,
+				[-lmkl_gf -lmkl_sequential -lmkl_core -lpthread])
+		fi
+	# MKL for other compilers (Intel, PGI, ...?)
+	else
+		# 64-bit
+		if test $host_cpu = x86_64; then
+			AC_CHECK_LIB(mkl_intel_lp64, $sgemm,
+				[ax_blas_ok=yes;BLAS_LIBS="-lmkl_intel_lp64 -lmkl_sequential -lmkl_core -lpthread"],,
+				[-lmkl_intel_lp64 -lmkl_sequential -lmkl_core -lpthread])
+		# 32-bit
+		elif test $host_cpu = i686; then
+			AC_CHECK_LIB(mkl_intel, $sgemm,
+				[ax_blas_ok=yes;BLAS_LIBS="-lmkl_intel -lmkl_sequential -lmkl_core -lpthread"],,
+				[-lmkl_intel -lmkl_sequential -lmkl_core -lpthread])
+		fi
+	fi
+fi
+# Old versions of MKL
+if test $ax_blas_ok = no; then
+	AC_CHECK_LIB(mkl, $sgemm, [ax_blas_ok=yes;BLAS_LIBS="-lmkl -lguide -lpthread"],,[-lguide -lpthread])
+fi
+
+# BLAS in Apple vecLib library?
+if test $ax_blas_ok = no; then
+	save_LIBS="$LIBS"; LIBS="-framework Accelerate $LIBS"
+	AC_MSG_CHECKING([for $sgemm in -framework Accelerate])
+	AC_LINK_IFELSE([AC_LANG_CALL([], [$sgemm])], [ax_blas_ok=yes;BLAS_LIBS="-framework Accelerate"])
+	AC_MSG_RESULT($ax_blas_ok)
+	LIBS="$save_LIBS"
+fi
+
+# BLAS in Alpha CXML library?
+if test $ax_blas_ok = no; then
+	AC_CHECK_LIB(cxml, $sgemm, [ax_blas_ok=yes;BLAS_LIBS="-lcxml"])
+fi
+
+# BLAS in Alpha DXML library? (now called CXML, see above)
+if test $ax_blas_ok = no; then
+	AC_CHECK_LIB(dxml, $sgemm, [ax_blas_ok=yes;BLAS_LIBS="-ldxml"])
+fi
+
+# BLAS in Sun Performance library?
+if test $ax_blas_ok = no; then
+	if test "x$GCC" != xyes; then # only works with Sun CC
+		AC_CHECK_LIB(sunmath, acosp,
+			[AC_CHECK_LIB(sunperf, $sgemm,
+				[BLAS_LIBS="-xlic_lib=sunperf -lsunmath"
+                                 ax_blas_ok=yes],[],[-lsunmath])])
+	fi
+fi
+
+# BLAS in SCSL library?  (SGI/Cray Scientific Library)
+if test $ax_blas_ok = no; then
+	AC_CHECK_LIB(scs, $sgemm, [ax_blas_ok=yes; BLAS_LIBS="-lscs"])
+fi
+
+# BLAS in SGIMATH library?
+if test $ax_blas_ok = no; then
+	AC_CHECK_LIB(complib.sgimath, $sgemm,
+		     [ax_blas_ok=yes; BLAS_LIBS="-lcomplib.sgimath"])
+fi
+
+# BLAS in IBM ESSL library? (requires generic BLAS lib, too)
+if test $ax_blas_ok = no; then
+	AC_CHECK_LIB(blas, $sgemm,
+		[AC_CHECK_LIB(essl, $sgemm,
+			[ax_blas_ok=yes; BLAS_LIBS="-lessl -lblas"],
+			[], [-lblas $FLIBS])])
+fi
+
+# Generic BLAS library?
+if test $ax_blas_ok = no; then
+	AC_CHECK_LIB(blas, $sgemm, [ax_blas_ok=yes; BLAS_LIBS="-lblas"])
+fi
+
+AC_SUBST(BLAS_LIBS)
+
+LIBS="$ax_blas_save_LIBS"
+
+# Finally, execute ACTION-IF-FOUND/ACTION-IF-NOT-FOUND:
+if test x"$ax_blas_ok" = xyes; then
+        ifelse([$1],,AC_DEFINE(HAVE_BLAS,1,[Define if you have a BLAS library.]),[$1])
+        :
+else
+        ax_blas_ok=no
+        $2
+fi
+])dnl AX_BLAS
diff --git a/m4/ax_lapack.m4 b/m4/ax_lapack.m4
new file mode 100644
index 00000000..cb296ef7
--- /dev/null
+++ b/m4/ax_lapack.m4
@@ -0,0 +1,122 @@
+dnl
+dnl				ax_lapack.m4
+dnl
+dnl Figure out if the OpenBLAS library and header files are installed.
+dnl
+dnl %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+dnl
+dnl	This file part of:	AstrOmatic software
+dnl
+dnl	Copyright:		(C) 2016 IAP/CNRS/UPMC
+dnl
+dnl	License:		GNU General Public License
+dnl
+dnl	AstrOmatic software is free software: you can redistribute it and/or
+dnl	modify it under the terms of the GNU General Public License as
+dnl	published by the Free Software Foundation, either version 3 of the
+dnl	License, or (at your option) any later version.
+dnl	AstrOmatic software is distributed in the hope that it will be useful,
+dnl	but WITHOUT ANY WARRANTY; without even the implied warranty of
+dnl	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+dnl	GNU General Public License for more details.
+dnl	You should have received a copy of the GNU General Public License
+dnl	along with AstrOmatic software.
+dnl	If not, see <http://www.gnu.org/licenses/>.
+dnl
+dnl	Last modified:		2025-07-21
+dnl
+dnl %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+dnl
+dnl @synopsis AX_LAPACK([LAPACK_LIBSDIR, LAPACK_INCDIR,
+dnl                  [ACTION-IF-FOUND[, ACTION-IF-NOT-FOUND]]])
+dnl
+dnl You may wish to use these variables in your default LIBS:
+dnl
+dnl        LIBS="$LAPACK_LIBS $LIBS"
+dnl
+dnl ACTION-IF-FOUND is a list of shell commands to run if LAPACK
+dnl is found (HAVE_LAPACK is defined first), and ACTION-IF-NOT-FOUND
+dnl is a list of commands to run it if it is not found.
+
+AC_DEFUN([AX_LAPACK], [
+AC_REQUIRE([AC_CANONICAL_HOST])
+
+dnl --------------------
+dnl Search include files
+dnl Under openSUSE and Fedora we have /usr/include/openblas/{lapack.h,lapacke.h,lapacke_config.h}
+dnl Under Ubuntu we have /usr/include/{lapack.h,lapacke.h,lapacke_64.h}
+dnl --------------------
+
+LAPACK_ERROR=""
+if test x$2 = x; then
+  [acx_lapack_incdir="openblas/"]
+  AC_CHECK_HEADERS(
+    [${acx_lapack_incdir}lapacke.h],,
+    [
+      [acx_lapack_incdir=""]
+      AC_CHECK_HEADER(
+        [lapacke.h],,
+        [LAPACK_ERROR="lapacke header files not found!"]
+      )
+    ]
+  )
+else
+  acx_lapack_incdir="$2/"
+  AC_CHECK_HEADER(
+    [${acx_lapack_incdir}lapacke.h],,
+    [
+      [acx_lapack_incdir="$2/include/"]
+      AC_CHECK_HEADERS(
+        [${acx_lapack_incdir}lapacke.h],,
+        [LAPACK_ERROR="lapacke header files not found in "$2"!"]
+    )]
+  )
+fi
+
+if test "x$LAPACK_ERROR" = "x"; then
+  AC_DEFINE_UNQUOTED(LAPACKE_H, "${acx_lapack_incdir}lapacke.h", [LAPACKe header filename.])
+  LAPACK_CFLAGS="-I ${acx_lapack_incdir}"
+
+dnl ----------------------------
+dnl Search lapack library file
+dnl On Fedora we have (dnf install lapack-devel) /usr/lib64/{liblapack64*,liblapack* ,liblapacke*}
+dnl On Ubuntu we have /usr/lib/x86_64-linux-gnu/liblapacke* 
+dnl    and /usr/lib/x86_64-linux-gnu/openblas-pthread/liblapack.so
+dnl On openSUSE we have /usr/lib64/lapack/liblapack.so.3, /usr/lib64/liblapack{e}.so
+dnl ----------------------------
+
+  OLIBS="$LIBS"
+  LIBS=""
+  if test x$1 = x; then
+    acx_lapack_libopt=""
+  else
+    acx_lapack_libopt="-L$1"
+  fi
+
+  AC_SEARCH_LIBS(
+    [LAPACKE_dpotrf], ["lapacke" "lapack" "openblas"],,
+    [LAPACK_ERROR="lapacke library file not found!"],
+    $acx_lapack_libopt
+  )
+  LIBS="$OLIBS"
+fi
+
+dnl -------------------------------------------------------------------------
+dnl Finally execute ACTION-IF-FOUND/ACTION-IF-NOT-FOUND
+dnl -------------------------------------------------------------------------
+
+if test "x$LAPACK_ERROR" = "x"; then
+  AC_DEFINE(HAVE_LAPACKE,1, [Define if you have the lapacke library and header files.])
+  LAPACK_LIBS="$ac_cv_search_LAPACKE_dpotrf"
+  AC_SUBST(LAPACK_CFLAGS)
+  AC_SUBST(LAPACK_LDFLAGS, $acx_lapack_libopt)
+  AC_SUBST(LAPACK_LIBS)
+  AC_SUBST(LAPACK_WARN)
+  $3
+else
+  AC_SUBST(LAPACK_ERROR)
+  $4
+fi
+
+])dnl AX_LAPACK
+