ENH: provide config setup for mesa with llvm (issue #1164)

- If using a non-clang compiler suite (gcc, intel, etc) the additional
  lbraries required for mesa with llvm pipelines may not be found.

  Provide a mesa_llvm configuration with in the 'vtk' config file.
  Can use the usual types of settings

     * mesa_llvm=llvm-4.0.1
     * mesa_llvm=none
     * mesa_llvm=system

etc/config.csh/vtk

@@ -2,7 +2,7 @@
 # =========                 |
 # \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
 #  \\    /   O peration     |
-#   \\  /    A nd           | Copyright (C) 2016-2017 OpenCFD Ltd.
+#   \\  /    A nd           | Copyright (C) 2016-2019 OpenCFD Ltd.
 #    \\/     M anipulation  |
 #------------------------------------------------------------------------------
 # License
@@ -32,31 +32,37 @@
 
 set vtk_version=VTK-8.2.0
 set mesa_version=mesa-17.1.1
+set mesa_llvm=none
 
-setenv VTK_DIR $WM_THIRD_PARTY_DIR/platforms/$WM_ARCH$WM_COMPILER/$vtk_version
-setenv MESA_ARCH_PATH $WM_THIRD_PARTY_DIR/platforms/$WM_ARCH$WM_COMPILER/$mesa_version
+setenv VTK_DIR "$WM_THIRD_PARTY_DIR/platforms/$WM_ARCH$WM_COMPILER/$vtk_version"
+setenv MESA_ARCH_PATH "$WM_THIRD_PARTY_DIR/platforms/$WM_ARCH$WM_COMPILER/$mesa_version"
+setenv LLVM_ARCH_PATH "$WM_THIRD_PARTY_DIR/platforms/$WM_ARCH/$mesa_llvm"
 
 # END OF (NORMAL) USER EDITABLE PART
 #------------------------------------------------------------------------------
 if ($?FOAM_VERBOSE && $?prompt) then
-    echo "Using vtk  ($vtk_version)  ->  $VTK_DIR"
-    echo "Using mesa ($mesa_version)  ->  $MESA_ARCH_PATH"
+    echo "Using vtk"
+    echo "    vtk  ($vtk_version) $VTK_DIR"
+    echo "    mesa ($mesa_version) $MESA_ARCH_PATH"
+    echo "    llvm ($mesa_llvm) $LLVM_ARCH_PATH"
 endif
 
 # Set paths if binaries are present
-if ( -r $VTK_DIR ) then
+if ( -d "$VTK_DIR" ) then
     # Uses lib/ and not lib64/
-    _foamAddLib $VTK_DIR/lib
+    _foamAddLib "$VTK_DIR/lib"
 else
     unset VTK_DIR
 endif
 
-if ( -r $MESA_ARCH_PATH ) then
-    _foamAddLib $MESA_ARCH_PATH/lib$WM_COMPILER_LIB_ARCH
+if ( -d "$MESA_ARCH_PATH" ) then
+    _foamAddLibAuto "$LLVM_ARCH_PATH"
+    _foamAddLibAuto "$MESA_ARCH_PATH"
 else
+    unset LLVM_ARCH_PATH
     unset MESA_ARCH_PATH
 endif
 
-unset vtk_version mesa_version
+unset vtk_version mesa_version mesa_llvm
 
 #------------------------------------------------------------------------------

etc/config.sh/vtk

@@ -2,7 +2,7 @@
 # =========                 |
 # \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
 #  \\    /   O peration     |
-#   \\  /    A nd           | Copyright (C) 2016-2017 OpenCFD Ltd.
+#   \\  /    A nd           | Copyright (C) 2016-2019 OpenCFD Ltd.
 #    \\/     M anipulation  |
 #------------------------------------------------------------------------------
 # License
@@ -33,38 +33,44 @@
 
 vtk_version=VTK-8.2.0
 mesa_version=mesa-17.1.1
+mesa_llvm=none
 
-export VTK_DIR=$WM_THIRD_PARTY_DIR/platforms/$WM_ARCH$WM_COMPILER/$vtk_version
-export MESA_ARCH_PATH=$WM_THIRD_PARTY_DIR/platforms/$WM_ARCH$WM_COMPILER/$mesa_version
+export VTK_DIR="$WM_THIRD_PARTY_DIR/platforms/$WM_ARCH$WM_COMPILER/$vtk_version"
+export MESA_ARCH_PATH="$WM_THIRD_PARTY_DIR/platforms/$WM_ARCH$WM_COMPILER/$mesa_version"
+export LLVM_ARCH_PATH="$WM_THIRD_PARTY_DIR/platforms/$WM_ARCH/$mesa_llvm"
 
 # END OF (NORMAL) USER EDITABLE PART
 #------------------------------------------------------------------------------
 if [ -n "$FOAM_VERBOSE" ] && [ -n "$PS1" ]
 then
-    echo "Using vtk  ($vtk_version)  ->  $VTK_DIR" 1>&2
-    echo "Using mesa ($mesa_version)  ->  $MESA_ARCH_PATH" 1>&2
+    echo "Using vtk" 1>&2
+    echo "    vtk  ($vtk_version) $VTK_DIR" 1>&2
+    echo "    mesa ($mesa_version) $MESA_ARCH_PATH" 1>&2
+    echo "    llvm ($mesa_llvm) $LLVM_ARCH_PATH" 1>&2
 fi
 
 if command -v _foamAddLib > /dev/null 2>&1  # normal sourcing
 then
 
     # Set paths if binaries are present
-    if [ -r $VTK_DIR ]
+    if [ -d "$VTK_DIR" ]
     then
         # Uses lib/ and not lib64/
-        _foamAddLib $VTK_DIR/lib
+        _foamAddLib "$VTK_DIR/lib"
     else
         unset VTK_DIR
     fi
 
-    if [ -r $MESA_ARCH_PATH ]
+    if [ -d "$MESA_ARCH_PATH" ]
     then
-        _foamAddLib $MESA_ARCH_PATH/lib$WM_COMPILER_LIB_ARCH
+        _foamAddLibAuto "$LLVM_ARCH_PATH"
+        _foamAddLibAuto "$MESA_ARCH_PATH"
     else
+        unset LLVM_ARCH_PATH
         unset MESA_ARCH_PATH
     fi
 
-    unset vtk_version mesa_version
+    unset vtk_version mesa_version mesa_llvm
 fi
 
 #------------------------------------------------------------------------------