From ae5fa4a042ab5f0884df2ee847de5825f94ab853 Mon Sep 17 00:00:00 2001
From: Ray Speth <speth@mit.edu>
Date: Mon, 24 Feb 2014 03:25:19 +0000
Subject: [PATCH] [SCons] Add test for Fortran library

Check for both the Fortran compiler and the corresponding Fortran library before
deciding whether to build the F90 interface. This will automatically disable the
F90 interface on platforms that provide gfortran but don't put libgfortran in a
standard location.
---
 SConstruct | 100 ++++++++++++++++++++++++++++++-----------------------
 1 file changed, 57 insertions(+), 43 deletions(-)

diff --git a/SConstruct b/SConstruct
index d44cd773f..702c29e4c 100644
--- a/SConstruct
+++ b/SConstruct
@@ -662,49 +662,6 @@ env['extra_lib_dirs'] = [d for d in env['extra_lib_dirs'].split(':') if d]
 env.Append(CPPPATH=env['extra_inc_dirs'],
            LIBPATH=env['extra_lib_dirs'])
 
-# Try to find a Fortran compiler:
-if env['f90_interface'] in ('y','default'):
-    foundF90 = False
-    if env['FORTRAN']:
-        env['f90_interface'] = 'y'
-        if which(env['FORTRAN']) is not None:
-            foundF90 = True
-        else:
-            print "WARNING: Couldn't find specified Fortran compiler: '%s'" % env['FORTRAN']
-
-    for compiler in ['gfortran', 'ifort', 'g95']:
-        if foundF90:
-            break
-        if which(compiler) is not None:
-            print "INFO: Using '%s' to build the Fortran 90 interface" % which(compiler)
-            env['FORTRAN'] = compiler
-            foundF90 = True
-
-    if foundF90:
-        env['f90_interface'] = 'y'
-    elif env['f90_interface'] == 'y':
-        print "ERROR: Couldn't find a suitable Fortran compiler to build the Fortran 90 interface."
-        sys.exit(1)
-    else:
-        print "INFO: Skipping compilation of the Fortran 90 interface."
-
-if 'gfortran' in env['FORTRAN']:
-    env['FORTRANMODDIRPREFIX'] = '-J'
-    env['FORTRANSYSLIBS'] = ['gfortran']
-elif 'g95' in env['FORTRAN']:
-    env['FORTRANMODDIRPREFIX'] = '-fmod='
-    env['FORTRANSYSLIBS'] = ['f95']
-elif 'ifort' in env['FORTRAN']:
-    env['FORTRANMODDIRPREFIX'] = '-module '
-    env['FORTRANSYSLIBS'] = []
-else:
-    env['FORTRANSYSLIBS'] = []
-
-env['F77'] = env['F90'] = env['F95'] = env['F03'] = env['FORTRAN']
-env['F77FLAGS'] = env['F90FLAGS'] = env['F95FLAGS'] = env['F03FLAGS'] = env['FORTRANFLAGS']
-
-env['FORTRANMODDIR'] = '${TARGET.dir}'
-
 if env['CC'] == 'cl':
     # embed manifest file
     env['LINKCOM'] = [env['LINKCOM'],
@@ -845,6 +802,63 @@ if env['HAS_SUNDIALS'] and env['use_sundials'] != 'n':
         print ('WARNING: External BLAS/LAPACK has been specified for Cantera '
                'but Sundials was built without this support.')
 
+# Try to find a working Fortran compiler:
+env['FORTRANSYSLIBS'] = []
+fortran_libs = {'gfortran':'gfortran', 'g95':'f95'}
+def check_fortran(compiler, expected=False):
+    if which(compiler) is not None:
+        lib = fortran_libs.get(compiler)
+        if lib:
+            have_lib = conf.CheckLib(lib)
+            if have_lib:
+                env.Append(FORTRANSYSLIBS=lib)
+                env['FORTRAN'] = compiler
+                return True
+            else:
+                print ("WARNING: Unable to use '%s' to compile the Fortran "
+                       "interface because the library '%s' could not be found." %
+                       (compiler, lib))
+        else:
+            env['FORTRAN'] = compiler
+            return True
+    elif expected:
+        print "WARNING: Couldn't find specified Fortran compiler: '%s'" % compiler
+
+    return False
+
+if env['f90_interface'] in ('y','default'):
+    foundF90 = False
+    if env['FORTRAN']:
+        foundF90 = check_fortran(env['FORTRAN'], True)
+
+    for compiler in ('gfortran', 'ifort', 'g95'):
+        if foundF90:
+            break
+        foundF90 = check_fortran(compiler)
+
+    if foundF90:
+        print "INFO: Using '%s' to build the Fortran 90 interface" % env['FORTRAN']
+        env['f90_interface'] = 'y'
+    else:
+        if env['f90_interface'] == 'y':
+            print "ERROR: Couldn't find a suitable Fortran compiler to build the Fortran 90 interface."
+            sys.exit(1)
+        else:
+            env['f90_interface'] = 'n'
+            print "INFO: Skipping compilation of the Fortran 90 interface."
+
+if 'gfortran' in env['FORTRAN']:
+    env['FORTRANMODDIRPREFIX'] = '-J'
+elif 'g95' in env['FORTRAN']:
+    env['FORTRANMODDIRPREFIX'] = '-fmod='
+elif 'ifort' in env['FORTRAN']:
+    env['FORTRANMODDIRPREFIX'] = '-module '
+
+env['F77'] = env['F90'] = env['F95'] = env['F03'] = env['FORTRAN']
+env['F77FLAGS'] = env['F90FLAGS'] = env['F95FLAGS'] = env['F03FLAGS'] = env['FORTRANFLAGS']
+
+env['FORTRANMODDIR'] = '${TARGET.dir}'
+
 env = conf.Finish()