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dnl -------------------------------------------------------------------------
dnl -------------------------------------------------------------------------
dnl
dnl Copyright by the Board of Trustees of the University of Illinois.
dnl All rights reserved.
dnl
dnl This file is part of HDF5.  The full HDF5 copyright notice, including
dnl terms governing use, modification, and redistribution, is contained in
dnl the COPYING file, which can be found at the root of the source code
dnl distribution tree, or in https://support.hdfgroup.org/ftp/HDF5/releases.
dnl If you do not have access to either file, you may request a copy from
dnl help@hdfgroup.org
dnl
dnl -------------------------------------------------------------------------
dnl -------------------------------------------------------------------------

dnl *********************************
dnl PURPOSE
dnl  Contains Macros for HDF5 Fortran
dnl *********************************
dnl
dnl Special characteristics that have no autoconf counterpart but that
dnl we need as part of the C++ support.  To distinquish these, they
dnl have a [PAC] prefix.
dnl
dnl -------------------------------------------------------------------------
dnl
dnl PAC_FC_SEARCH_LIST - expands to a whitespace separated list of modern
dnl fortran compilers for use with AC_PROG_FC that is more suitable for HPC
dnl software packages
AC_DEFUN([PAC_FC_SEARCH_LIST],
         [gfortran ifort pgf90 pathf90 pathf95 xlf90 xlf95 xlf2003 f90 epcf90 f95 fort lf95 g95 ifc efc gfc])
dnl 
dnl PAC_PROG_FC([COMPILERS])
dnl
dnl COMPILERS is a space separated list of Fortran compilers to search for.
dnl
dnl Compilers are ordered by
dnl  1. F90, F95, F2003
dnl  2. Good/tested native compilers, bad/untested native compilers
dnl  3. Wrappers around f2c go last.
dnl
dnl frt is the Fujitsu Fortran compiler.
dnl pgf90 are the Portland Group F90 compilers.
dnl xlf/xlf90/xlf95/xlf2003 are IBM (AIX) F90/F95/F2003 compilers.
dnl lf95 is the Lahey-Fujitsu compiler.
dnl fl32 is the Microsoft Fortran "PowerStation" compiler.
dnl epcf90 is the "Edinburgh Portable Compiler" F90.
dnl fort is the Compaq Fortran 90 (now 95) compiler for Tru64 and Linux/Alpha.
dnl pathf90 is the Pathscale Fortran 90 compiler
dnl ifort is another name for the Intel f90 compiler
dnl efc - An older Intel compiler (?)
dnl ifc - An older Intel compiler
dnl fc  - A compiler on some unknown system.  This has been removed because
dnl       it may also be the name of a command for something other than
dnl       the Fortran compiler (e.g., fc=file system check!)
dnl gfortran - The GNU Fortran compiler (not the same as g95) 
dnl gfc - An alias for gfortran recommended in cygwin installations
dnl NOTE: this macro suffers from a basically intractable "expanded before it
dnl was required" problem when libtool is also used 
dnl [1] MPICH.org
dnl

dnl See if the fortran compiler supports the intrinsic module "ISO_FORTRAN_ENV"

AC_DEFUN([PAC_PROG_FC_ISO_FORTRAN_ENV],[
  HAVE_ISO_FORTRAN_ENV="no"
  AC_MSG_CHECKING([if Fortran compiler supports intrinsic module ISO_FORTRAN_ENV])
  TEST_SRC="`sed -n '/PROGRAM PROG_FC_ISO_FORTRAN_ENV/,/END PROGRAM PROG_FC_ISO_FORTRAN_ENV/p' $srcdir/m4/aclocal_fc.f90`"	
  AC_LINK_IFELSE([$TEST_SRC],[AC_MSG_RESULT([yes])
     	HAVE_ISO_FORTRAN_ENV="yes"],
      [AC_MSG_RESULT([no])])
])

dnl See if the fortran compiler supports the intrinsic function "SIZEOF"

AC_DEFUN([PAC_PROG_FC_SIZEOF],[
  HAVE_SIZEOF_FORTRAN="no"
  AC_MSG_CHECKING([if Fortran compiler supports intrinsic SIZEOF])
  TEST_SRC="`sed -n '/PROGRAM PROG_FC_SIZEOF/,/END PROGRAM PROG_FC_SIZEOF/p' $srcdir/m4/aclocal_fc.f90`"
  AC_LINK_IFELSE([$TEST_SRC],[AC_MSG_RESULT([yes])
     	HAVE_SIZEOF_FORTRAN="yes"],
      [AC_MSG_RESULT([no])])
])

dnl See if the fortran compiler supports the intrinsic function "C_SIZEOF"

AC_DEFUN([PAC_PROG_FC_C_SIZEOF],[
  HAVE_C_SIZEOF_FORTRAN="no"
  AC_MSG_CHECKING([if Fortran compiler supports intrinsic C_SIZEOF])
  TEST_SRC="`sed -n '/PROGRAM PROG_FC_C_SIZEOF/,/END PROGRAM PROG_FC_C_SIZEOF/p' $srcdir/m4/aclocal_fc.f90`"
  AC_LINK_IFELSE([$TEST_SRC], [AC_MSG_RESULT([yes])
     	HAVE_C_SIZEOF_FORTRAN="yes"],
     [AC_MSG_RESULT([no])])
])

dnl See if the fortran compiler supports the intrinsic function "STORAGE_SIZE"

AC_DEFUN([PAC_PROG_FC_STORAGE_SIZE],[
  HAVE_STORAGE_SIZE_FORTRAN="no"
  AC_MSG_CHECKING([if Fortran compiler supports intrinsic STORAGE_SIZE])
  TEST_SRC="`sed -ne '/PROGRAM PROG_FC_STORAGE_SIZE/,/END PROGRAM PROG_FC_STORAGE_SIZE/p' $srcdir/m4/aclocal_fc.f90`"
  AC_LINK_IFELSE([$TEST_SRC], [AC_MSG_RESULT([yes])
     	HAVE_STORAGE_SIZE_FORTRAN="yes"],
     [AC_MSG_RESULT([no])])

])

dnl Check to see C_LONG_DOUBLE is available

AC_DEFUN([PAC_PROG_FC_HAVE_C_LONG_DOUBLE],[
  HAVE_C_LONG_DOUBLE_FORTRAN="no"
  AC_MSG_CHECKING([if Fortran compiler supports intrinsic C_LONG_DOUBLE])
  TEST_SRC=""
  TEST_SRC="`sed -n '/PROGRAM PROG_FC_HAVE_C_LONG_DOUBLE/,/END PROGRAM PROG_FC_HAVE_C_LONG_DOUBLE/p' $srcdir/m4/aclocal_fc.f90`"
  AC_LINK_IFELSE([$TEST_SRC], [AC_MSG_RESULT([yes])
     	HAVE_C_LONG_DOUBLE_FORTRAN="yes"],
     [AC_MSG_RESULT([no])])
])

dnl Check if C_LONG_DOUBLE is different from C_DOUBLE

if  test "X$FORTRAN_HAVE_C_LONG_DOUBLE" = "Xyes"; then
AC_DEFUN([PAC_PROG_FC_C_LONG_DOUBLE_EQ_C_DOUBLE],[
  C_LONG_DOUBLE_IS_UNIQUE_FORTRAN="no"	
  AC_MSG_CHECKING([if Fortran C_LONG_DOUBLE is different from C_DOUBLE])
  TEST_SRC="`sed -n '/MODULE type_mod/,/END PROGRAM PROG_FC_C_LONG_DOUBLE_EQ_C_DOUBLE/p' $srcdir/m4/aclocal_fc.f90`"
  AC_COMPILE_IFELSE([$TEST_SRC], [AC_MSG_RESULT([yes]) 
            C_LONG_DOUBLE_IS_UNIQUE_FORTRAN="yes"], 
         [AC_MSG_RESULT([no])])
])
fi

dnl Checking if the compiler supports the required Fortran 2003 features and
dnl disable Fortran 2003 if it does not.

AC_DEFUN([PAC_PROG_FC_HAVE_F2003_REQUIREMENTS],[
   HAVE_F2003_REQUIREMENTS="no"
   AC_MSG_CHECKING([if Fortran compiler version compatible with Fortran 2003 HDF])
   TEST_SRC="`sed -n '/PROG_FC_HAVE_F2003_REQUIREMENTS/,/END PROGRAM PROG_FC_HAVE_F2003_REQUIREMENTS/p' $srcdir/m4/aclocal_fc.f90`"
   AC_COMPILE_IFELSE([$TEST_SRC], [AC_MSG_RESULT([yes]) 
            HAVE_F2003_REQUIREMENTS="yes"], 
         [AC_MSG_RESULT([no])])
])

dnl -------------------------------------------------------------------------
dnl AC_F9X_MODS()
dnl
dnl	Check how F9X handles modules. This macro also checks which
dnl	command-line option to use to include the module once it's built.
dnl
AC_DEFUN([AC_F9X_MODS],
[AC_MSG_CHECKING(what $FC does with modules)
AC_LANG_PUSH(Fortran)

test -d conftestdir || mkdir conftestdir
cd conftestdir
rm -rf *

cat >conftest.$ac_ext <<EOF
      module module
         integer foo
      end module module
EOF

eval $ac_compile
modfiles=""
F9XMODEXT=""

for f in conftest.o module.mod MODULE.mod module.M MODULE.M; do
  if test -f "$f" ; then
    modfiles="$f"

    case "$f" in
      *.o)   F9XMODEXT="o" ;;
      *.mod) F9XMODEXT="mod" ;;
      *.M)   F9XMODEXT="M" ;;
    esac
  fi
done

echo $modfiles 6>&1
if test "$modfiles" = file.o; then
  echo $ac_n "checking whether $FC -em is saner""... $ac_c" 1>&6
  OLD_FCFLAGS=$FCFLAGS
  FCFLAGS="$FCFLAGS -em"
  eval $ac_compile
  modfiles=""
  for f in file.o module.mod MODULE.mod module.M MODULE.M; do
    test -f $f && modfiles="$f"
  done
  if test "$modfiles" = "file.o"; then
    FCFLAGS=$OLD_FCFLAGS
    echo no 6>&1
  else
    echo yes 6>&1
  fi
fi
cd ..

AC_MSG_CHECKING(how $FC finds modules)

for flag in "-I" "-M" "-p"; do
  cat >conftest.$ac_ext <<EOF
      program conftest
          use module
      end program conftest
EOF

  ac_compile='${FC-f90} $FCFLAGS ${flag}conftestdir -c conftest.$ac_ext 1>&AS_MESSAGE_LOG_FD'

  if AC_TRY_EVAL(ac_compile); then
    F9XMODFLAG=$flag
    break
  fi
done

if test -n "$F9XMODFLAG"; then
  echo $F9XMODFLAG 1>&6
  FCFLAGS="$F9XMODFLAG. $FCFLAGS"
else
  echo unknown 1>&6
fi
AC_SUBST(F9XMODFLAG)
AC_SUBST(F9XMODEXT)
rm -rf conftest*
AC_LANG_POP(Fortran)
])

dnl ----------------------
dnl Parallel Test Programs
dnl ----------------------

dnl Try link a simple MPI program.

AC_DEFUN([PAC_PROG_FC_MPI_CHECK],[

dnl   Change to the Fortran 90 language
      AC_LANG_PUSH(Fortran)
      TEST_SRC="`sed -n '/PROGRAM FC_MPI_CHECK/,/END PROGRAM FC_MPI_CHECK/p' $srcdir/m4/aclocal_fc.f90`"
dnl   Try link a simple MPI program.
      AC_MSG_CHECKING([whether a simple MPI-IO Fortran program can be linked])
      AC_LINK_IFELSE([$TEST_SRC],
	  [AC_MSG_RESULT([yes])],
	  [AC_MSG_RESULT([no])
	   AC_MSG_ERROR([unable to link a simple MPI-IO Fortran program])])

dnl   Change to the C language
      AC_LANG_POP(Fortran)
])

dnl ------------------------------------------------------
dnl Determine the available KINDs for REALs and INTEGERs
dnl ------------------------------------------------------
dnl
dnl This is a runtime test.
dnl
AC_DEFUN([PAC_FC_AVAIL_KINDS],[
AC_LANG_PUSH([Fortran])
rm -f pac_fconftest.out
TEST_SRC="`sed -n '/PROGRAM FC_AVAIL_KINDS/,/END PROGRAM FC_AVAIL_KINDS/p' $srcdir/m4/aclocal_fc.f90`"
AC_RUN_IFELSE([$TEST_SRC],
 [
    if test -s pac_fconftest.out ; then
	
     dnl The output from the above program will be:
     dnl    -- LINE 1 --  valid integer kinds (comma seperated list)
     dnl    -- LINE 2 --  valid real kinds (comma seperated list)
     dnl    -- LINE 3 --  max decimal precision for reals
     dnl    -- LINE 4 --  number of valid integer kinds
     dnl    -- LINE 5 --  number of valid real kinds

        pac_validIntKinds="`sed -n '1p' pac_fconftest.out`"
	pac_validRealKinds="`sed -n '2p' pac_fconftest.out`"
        PAC_FC_MAX_REAL_PRECISION="`sed -n '3p' pac_fconftest.out`"
        AC_DEFINE_UNQUOTED([PAC_FC_MAX_REAL_PRECISION], $PAC_FC_MAX_REAL_PRECISION, [Define Fortran Maximum Real Decimal Precision])

        PAC_FC_ALL_INTEGER_KINDS="{`echo $pac_validIntKinds`}"
        PAC_FC_ALL_REAL_KINDS="{`echo $pac_validRealKinds`}"

        PAC_FORTRAN_NUM_INTEGER_KINDS="`sed -n '4p' pac_fconftest.out`"
	H5CONFIG_F_NUM_IKIND="INTEGER, PARAMETER :: num_ikinds = `echo $PAC_FORTRAN_NUM_INTEGER_KINDS`"
	H5CONFIG_F_IKIND="INTEGER, DIMENSION(1:num_ikinds) :: ikind = (/`echo $pac_validIntKinds`/)"
	H5CONFIG_F_NUM_RKIND="INTEGER, PARAMETER :: num_rkinds = `sed -n '5p' pac_fconftest.out`"
	H5CONFIG_F_RKIND="INTEGER, DIMENSION(1:num_rkinds) :: rkind = (/`echo $pac_validRealKinds`/)"

	AC_DEFINE_UNQUOTED([H5CONFIG_F_NUM_RKIND], $H5CONFIG_F_NUM_RKIND, [Define number of valid Fortran REAL KINDs])
	AC_DEFINE_UNQUOTED([H5CONFIG_F_NUM_IKIND], $H5CONFIG_F_NUM_IKIND, [Define number of valid Fortran INTEGER KINDs])
	AC_DEFINE_UNQUOTED([H5CONFIG_F_RKIND], $H5CONFIG_F_RKIND, [Define valid Fortran REAL KINDs])
	AC_DEFINE_UNQUOTED([H5CONFIG_F_IKIND], $H5CONFIG_F_IKIND, [Define valid Fortran INTEGER KINDs])

        AC_MSG_CHECKING([for Number of Fortran INTEGER KINDs])
        AC_MSG_RESULT([$PAC_FORTRAN_NUM_INTEGER_KINDS])
        AC_MSG_CHECKING([for Fortran INTEGER KINDs])
        AC_MSG_RESULT([$PAC_FC_ALL_INTEGER_KINDS])
	AC_MSG_CHECKING([for Fortran REAL KINDs])
	AC_MSG_RESULT([$PAC_FC_ALL_REAL_KINDS])
	AC_MSG_CHECKING([for Fortran REALs maximum decimal precision])
	AC_MSG_RESULT([$PAC_FC_MAX_REAL_PRECISION])
    else
        AC_MSG_RESULT([Error])
        AC_MSG_ERROR([No output from Fortran test program!])
    fi
    rm -f pac_fconftest.out
],[
    AC_MSG_RESULT([Error])
    AC_MSG_ERROR([Failed to run Fortran program to determine available KINDs])
],[])

AC_LANG_POP([Fortran])
])
AC_DEFUN([PAC_FC_SIZEOF_INT_KINDS],[
AC_REQUIRE([PAC_FC_AVAIL_KINDS])
AC_MSG_CHECKING([sizeof of available INTEGER KINDs])
AC_LANG_PUSH([Fortran])
pack_int_sizeof=""
rm -f pac_fconftest.out

for kind in `echo $pac_validIntKinds | sed -e 's/,/ /g'`; do
  AC_LANG_CONFTEST([
      AC_LANG_SOURCE([
                PROGRAM main
                USE ISO_C_BINDING
                IMPLICIT NONE
                INTEGER (KIND=$kind) a
                OPEN(8, FILE='pac_fconftest.out', FORM='formatted')
                WRITE(8,'(I0)') $FC_SIZEOF_A
                CLOSE(8)
                END
            ])
        ])
        AC_RUN_IFELSE([],[
            if test -s pac_fconftest.out ; then
                sizes="`cat pac_fconftest.out`"
                pack_int_sizeof="$pack_int_sizeof $sizes,"
            else
                AC_MSG_ERROR([No output from Fortran test program!])
            fi
            rm -f pac_fconftest.out
        ],[
            AC_MSG_ERROR([Fortran program fails to build or run!])
        ],[
            pack_int_sizeof="$2"
        ])
done
PAC_FC_ALL_INTEGER_KINDS_SIZEOF="{`echo $pack_int_sizeof | sed -e 's/,$//' | sed -e 's/ //g'`}"
AC_MSG_RESULT([$PAC_FC_ALL_INTEGER_KINDS_SIZEOF])
AC_LANG_POP([Fortran])
])

AC_DEFUN([PAC_FC_SIZEOF_REAL_KINDS],[
AC_REQUIRE([PAC_FC_AVAIL_KINDS])
AC_MSG_CHECKING([sizeof of available REAL KINDs])
AC_LANG_PUSH([Fortran])
pack_real_sizeof=""
rm -f pac_fconftest.out
for kind in `echo  $pac_validRealKinds | sed -e 's/,/ /g'`; do
  AC_LANG_CONFTEST([
      AC_LANG_SOURCE([
                PROGRAM main
                USE ISO_C_BINDING
                IMPLICIT NONE
                REAL (KIND=$kind) :: a
                OPEN(8, FILE='pac_fconftest.out', FORM='formatted')
                WRITE(8,'(I0)') $FC_SIZEOF_A
                CLOSE(8)
                END
            ])
        ])
        AC_RUN_IFELSE([],[
            if test -s pac_fconftest.out ; then
                sizes="`cat pac_fconftest.out`"
                pack_real_sizeof="$pack_real_sizeof $sizes,"
            else
                AC_MSG_ERROR([No output from Fortran test program!])
            fi
            rm -f pac_fconftest.out
        ],[
            AC_MSG_ERROR([Fortran program fails to build or run!])
        ],[
            pack_real_sizeof="$2"
        ])
done
PAC_FC_ALL_REAL_KINDS_SIZEOF="{`echo $pack_real_sizeof | sed -e 's/,$//' | sed -e 's/ //g'`}"
AC_MSG_RESULT([$PAC_FC_ALL_REAL_KINDS_SIZEOF])
AC_LANG_POP([Fortran])
])

AC_DEFUN([PAC_FC_NATIVE_INTEGER],[
AC_REQUIRE([PAC_FC_AVAIL_KINDS])
AC_MSG_CHECKING([sizeof of native KINDS])
AC_LANG_PUSH([Fortran])
pack_int_sizeof=""
rm -f pac_fconftest.out
  AC_LANG_CONFTEST([
      AC_LANG_SOURCE([
                PROGRAM main
                USE ISO_C_BINDING
                IMPLICIT NONE
                INTEGER a
                REAL b
                DOUBLE PRECISION c
                OPEN(8, FILE='pac_fconftest.out', FORM='formatted')
                WRITE(8,*) $FC_SIZEOF_A
	        WRITE(8,*) KIND(a)
	        WRITE(8,*) $FC_SIZEOF_B
	        WRITE(8,*) KIND(b)
                WRITE(8,*) $FC_SIZEOF_C
                WRITE(8,*) KIND(c)
                CLOSE(8)
                END
            ])
        ])
        AC_RUN_IFELSE([],[
            if test -s pac_fconftest.out ; then
                PAC_FORTRAN_NATIVE_INTEGER_SIZEOF="`sed -n '1p' pac_fconftest.out`"
                PAC_FORTRAN_NATIVE_INTEGER_KIND="`sed -n '2p' pac_fconftest.out`"
                PAC_FORTRAN_NATIVE_REAL_SIZEOF="`sed -n '3p' pac_fconftest.out`"
                PAC_FORTRAN_NATIVE_REAL_KIND="`sed -n '4p' pac_fconftest.out`"
                PAC_FORTRAN_NATIVE_DOUBLE_SIZEOF="`sed -n '5p' pac_fconftest.out`"
                PAC_FORTRAN_NATIVE_DOUBLE_KIND="`sed -n '6p' pac_fconftest.out`"
            else
                AC_MSG_ERROR([No output from Fortran test program!])
            fi
            rm -f pac_fconftest.out
        ],[
            AC_MSG_ERROR([Fortran program fails to build or run!])
        ],[
            pack_int_sizeof="$2"
        ])
AC_MSG_RESULT([$pack_int_sizeof])
AC_LANG_POP([Fortran])
])

AC_DEFUN([PAC_FC_LDBL_DIG],[
AC_MSG_CHECKING([maximum decimal precision for C])
rm -f pac_Cconftest.out
  AC_LANG_CONFTEST([
      AC_LANG_PROGRAM([
                #include <float.h>
                #include <stdio.h>
                #define CHECK_FLOAT128 $ac_cv_sizeof___float128
                #if CHECK_FLOAT128!=0
                # if $HAVE_QUADMATH!=0
                #include <quadmath.h>
                # endif
                # ifdef FLT128_DIG
                #define C_FLT128_DIG FLT128_DIG
                # else
                #define C_FLT128_DIG 0
                # endif
                #else
                #define C_FLT128_DIG 0
                #endif
                #if defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
                #define C_LDBL_DIG DECIMAL_DIG 
                #else
                #define C_LDBL_DIG LDBL_DIG
                #endif
                ],[[
                  FILE * pFile;
                  pFile = fopen("pac_Cconftest.out","w");
                  fprintf(pFile, "%d\n%d\n", C_LDBL_DIG, C_FLT128_DIG);
                ]])
        ])
        AC_RUN_IFELSE([],[
            if test -s pac_Cconftest.out ; then
	        LDBL_DIG="`sed -n '1p' pac_Cconftest.out`" 
	        FLT128_DIG="`sed -n '2p' pac_Cconftest.out`"
            else
                AC_MSG_ERROR([No output from C decimal precision program!])
            fi
            rm -f pac_Cconftest.out
        ],[
            AC_MSG_ERROR([C program fails to build or run!])
        ],[])
])