gfrotran wrapper tool recognizes FASTR_FC, which allows to override the Fortran compiler

Author: steve-s

com.oracle.truffle.r.native/run/fastr_etc/Darwin/Makeconf.llvm

@@ -1,5 +1,5 @@
 #
-# Copyright (c) 2019, 2019, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2019, 2020, Oracle and/or its affiliates. All rights reserved.
 # DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 #
 # This code is free software; you can redistribute it and/or modify it

com.oracle.truffle.r.native/run/fastr_etc/Darwin/Makeconf.native

@@ -1,5 +1,5 @@
 #
-# Copyright (c) 2019, 2019, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2019, 2020, Oracle and/or its affiliates. All rights reserved.
 # DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 #
 # This code is free software; you can redistribute it and/or modify it

com.oracle.truffle.r.native/run/fastr_etc/Linux/Makeconf.llvm

@@ -1,5 +1,5 @@
 #
-# Copyright (c) 2019, 2019, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2019, 2020, Oracle and/or its affiliates. All rights reserved.
 # DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 #
 # This code is free software; you can redistribute it and/or modify it

com.oracle.truffle.r.native/run/fastr_etc/Linux/Makeconf.native

@@ -1,5 +1,5 @@
 #
-# Copyright (c) 2019, 2019, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2019, 2020, Oracle and/or its affiliates. All rights reserved.
 # DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 #
 # This code is free software; you can redistribute it and/or modify it

com.oracle.truffle.r.native/run/fastr_tools/safe-forward-gfortran

@@ -1,6 +1,6 @@
 #!/bin/sh
 #
-# Copyright (c) 2019, 2019, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2019, 2020, Oracle and/or its affiliates. All rights reserved.
 # DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 #
 # This code is free software; you can redistribute it and/or modify it
@@ -27,7 +27,9 @@
 # We do not use the generic safe-forward-tool, because we expect gfortran to be by far the
 # most problematic tool and we want to provide some more gfortan specific guidance.
 
-if command -v gfortran>/dev/null; then
+if [ "${FASTR_FC+dummy}" != dummy ]; then
+  exec "$FASTR_FC" "$@"
+elif command -v gfortran>/dev/null; then
   exec gfortran "$@"
 else
   >&2 echo "R package installation or similar process tried to use the 'gfortran' tool, the Fortran compiler from the GNU Compiler Collection (GCC)."