BACKPORT: config script bugfixes

- align with fixes for v2112 - align foamConfigurePaths with v2112 modifications CONFIG: scan scotch-64.h as possible fallback (#1904) - For RedHat 8, the /usr/include/scotch.h is actually wrapped with a condition check based on LP64 vs ILP32, so need to check with those headers if the first one failed.
2025-11-28 03:28:01 +00:00 · 2021-12-10 13:52:36 +01:00
parent 42178fdd5d
commit 0bd1b0feac
8 changed files with 607 additions and 311 deletions
--- a/bin/tools/foamConfigurePaths
+++ b/bin/tools/foamConfigurePaths
@ -7,7 +7,7 @@
 #    \\/     M anipulation  |
 #------------------------------------------------------------------------------
 #     Copyright (C) 2011-2016 OpenFOAM Foundation
-#     Copyright (C) 2016-2020 OpenCFD Ltd.
+#     Copyright (C) 2016-2021 OpenCFD Ltd.
 #------------------------------------------------------------------------------
 # License
 #     This file is part of OpenFOAM, distributed under GPL-3.0-or-later.
@ -42,11 +42,11 @@ printHelp() {
 Obsolete options:
  -foamInstall DIR    [obsolete]
  -projectName NAME   [obsolete]
-  -sigfpe|-no-sigfpe  [obsolete - now under etc/controlDict]
-  -archOption 32|64   [obsolete setting of 'WM_ARCH_OPTION' - edit manually]
+  -sigfpe|-no-sigfpe  [obsolete] now under etc/controlDict
+  -archOption 32|64   [obsolete] now edit WM_ARCH_OPTION manually

 Equivalent options:
-  -version -foamVersion --projectVersion
+  -version              --projectVersion | -foamVersion
  -archOption           --archOption
  -third                -ThirdParty
  -paraview             --paraviewVersion | -paraviewVersion
@ -55,6 +55,8 @@ Equivalent options:
  -scotch-path          --scotchArchPath | -scotchArchPath
  -system-compiler      -system
  -third-compiler       -third
+  -sys-openmpi          -openmpi-system
+  -openmpi              -openmpi-third

 HELP_COMPAT
        exit 0 # A clean exit
@ -89,10 +91,9 @@ Compiler
  mpc-VERSION         For ThirdParty gcc (mpc-system for system library)

 MPI
-  -mpi NAME           specify 'WM_MPLIB' type (eg, INTELMPI, etc)
-  -openmpi VER        use ThirdParty openmpi, with version for 'FOAM_MPI'
-  -openmpi-system     use system openmpi
-  -openmpi-third      use ThirdParty openmpi (using default version)
+  -mpi=NAME           Specify 'WM_MPLIB' type (eg, INTELMPI, etc)
+  -openmpi[=VER]      Use ThirdParty openmpi, with version for 'FOAM_MPI'
+  -sys-openmpi[=MAJ]  Use system openmpi, with specified major version

 Components versions (ThirdParty)
  -adios VER          specify 'adios2_version'
@ -120,12 +121,12 @@ Components specified by absolute path
  -scotch-path DIR    Path for 'SCOTCH_ARCH_PATH' (overrides -scotch)

 Graphics
-  -paraview VER       specify 'ParaView_VERSION' (eg, 5.4.1 or system)
+  -paraview VER       specify 'ParaView_VERSION' (eg, 5.9.0 or system)
  -paraview-qt VER    specify 'ParaView_QT' (eg, qt-system)
-  -paraview-path DIR  specify 'ParaView_DIR' (eg, /opt/ParaView-5.4.1)
+  -paraview-path DIR  specify 'ParaView_DIR' (eg, /opt/ParaView-5.9.0)
  -llvm VER           specify 'mesa_llvm'
  -mesa VER           specify 'mesa_version' (eg, mesa-13.0.1)
-  -vtk  VER           specify 'vtk_version' (eg, VTK-7.1.0)
+  -vtk  VER           specify 'vtk_version' (eg, VTK-9.0.0)
  -llvm-path DIR      Path for 'LLVM_ARCH_PATH'   (overrides -llvm)
  -mesa-path DIR      Path for 'MESA_ARCH_PATH'   (overrides -mesa)
  -vtk-path DIR       Path for 'VTK_DIR'          (overrides -vtk)
@ -212,12 +213,13 @@ _inlineSed()
    # Local filename (for reporting)
    localFile="$(echo "$file" | sed -e "s#^$projectDir/##")"

-    grep -q "$regexp" "$file" && sed -i -e "$cmd" "$file" || { \
+    if grep -q "$regexp" "$file" && sed -i -e "$cmd" "$file"
+    then
+        [ -n "$msg" ] && echo "    $msg  ($localFile)"
+    else
        echo "Failed: ${msg:-replacement} in $localFile"
        return 1
-    }
-
-    [ -n "$msg" ] && echo "    $msg  ($localFile)"
+    fi

    return 0
 }
@ -278,8 +280,8 @@ replaceEtc()
    local file="$1"
    shift

-    file=$(_foamEtc "$file")
-    replace $file "$@"
+    file="$(_foamEtc "$file")"
+    replace "$file" "$@"
 }


@ -289,24 +291,36 @@ replaceEtcCsh()
    local file="$1"
    shift

-    file=$(_foamEtc "$file")
-    replaceCsh $file "$@"
+    file="$(_foamEtc "$file")"
+    replaceCsh "$file" "$@"
 }


 # Get the option's value (argument), or die on missing or empty argument
 # $1 option
 # $2 value
+
+# Returns values via optValue, nOptArgs variables!!
+optValue=""
+nOptArgs=0  # The number of args to shift
+
 getOptionValue()
 {
-    local value="$2"
-    [ -n "$value" ] || die "'$1' option requires an argument"
+    optValue="${1#*=}"
+    if [ "$optValue" = "$1" ]
+    then
+        # Eg, -option value
+        optValue="$2"
+        [ -n "$optValue" ] || die "'$1' option requires an argument"
+        nOptArgs=1
+    else
+        # Eg, -option=value
+        nOptArgs=0
+    fi

    # Remove any surrounding double quotes
-    value="${value%\"}"
-    value="${value#\"}"
-
-    echo "$value"
+    optValue="${optValue%\"}"
+    optValue="${optValue#\"}"
 }


@ -366,7 +380,7 @@ removeCshMagic()

 #------------------------------------------------------------------------------

-unset adjusted optMpi
+unset adjusted
 # Parse options
 while [ "$#" -gt 0 ]
 do
@ -421,26 +435,37 @@ CONFIG_CSH
        [ -n "$FOAM_CONFIG_ETC" ] || unset FOAM_CONFIG_ETC
        ;;

-   -project-path)
+   -project-path=* | -project-path)
        # Replace WM_PROJECT_DIR=...
-        optionValue=$(getOptionValue "$@")
-        replaceEtc     bashrc  WM_PROJECT_DIR "\"$optionValue\""
-        replaceEtcCsh  cshrc   WM_PROJECT_DIR "\"$optionValue\""
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"

-        removeBashMagic $(_foamEtc bashrc)
-        removeCshMagic  $(_foamEtc cshrc)
+        if [ -n "$optValue" ]
+        then
+            replaceEtc     bashrc  WM_PROJECT_DIR "\"$optValue\""
+            replaceEtcCsh  cshrc   WM_PROJECT_DIR "\"$optValue\""

-        adjusted=true
-        shift
+            removeBashMagic "$(_foamEtc bashrc)"
+            removeCshMagic  "$(_foamEtc cshrc)"
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

-   -version | -foamVersion | --projectVersion)
+   -version=* | -version | -foamVersion | --projectVersion)
        # Replace WM_PROJECT_VERSION=...
-        optionValue=$(getOptionValue "$@")
-        replaceEtc     bashrc  WM_PROJECT_VERSION "$optionValue"
-        replaceEtcCsh  cshrc   WM_PROJECT_VERSION "$optionValue"
-        adjusted=true
-        shift
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
+        if [ -n "$optValue" ]
+        then
+            replaceEtc     bashrc  WM_PROJECT_VERSION "$optValue"
+            replaceEtcCsh  cshrc   WM_PROJECT_VERSION "$optValue"
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -sp | -SP | -float32)
@ -466,131 +491,168 @@ CONFIG_CSH

    -int32 | -int64)
        # Replace WM_LABEL_SIZE=...
-        optionValue="${1#-int}"
-        replaceEtc     bashrc  WM_LABEL_SIZE "$optionValue"
-        replaceEtcCsh  cshrc   WM_LABEL_SIZE "$optionValue"
+        optValue="${1#-int}"
+        replaceEtc     bashrc  WM_LABEL_SIZE "$optValue"
+        replaceEtcCsh  cshrc   WM_LABEL_SIZE "$optValue"
        adjusted=true
        ;;


 ## Compiler ##

-    -clang)
+    -clang=* | -clang)
        # Replace default_clang_version=...
-        optionValue=$(getOptionValue "$@")
-        replaceEtc  config.sh/compiler   default_clang_version "$optionValue"
-        replaceEtc  config.csh/compiler  default_clang_version "$optionValue"
-        adjusted=true
-        shift
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
+        if [ -n "$optValue" ]
+        then
+            replaceEtc  config.sh/compiler   default_clang_version "$optValue"
+            replaceEtc  config.csh/compiler  default_clang_version "$optValue"
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

-    -gcc)
+    -gcc=* | -gcc)
        # Replace default_gcc_version=...
-        optionValue=$(getOptionValue "$@")
-        replaceEtc  config.sh/compiler   default_gcc_version "$optionValue"
-        replaceEtc  config.csh/compiler  default_gcc_version "$optionValue"
-        adjusted=true
-        shift
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
+        if [ -n "$optValue" ]
+        then
+            replaceEtc  config.sh/compiler   default_gcc_version "$optValue"
+            replaceEtc  config.csh/compiler  default_gcc_version "$optValue"
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -system-compiler | -system)
        # Replace WM_COMPILER_TYPE=... and WM_COMPILER=...
-        optionValue=$(getOptionValue "$@")
-        replaceEtc  bashrc  \
-            WM_COMPILER_TYPE system \
-            WM_COMPILER "$optionValue"
-        replaceEtcCsh  cshrc \
-            WM_COMPILER_TYPE system \
-            WM_COMPILER "$optionValue"
-        adjusted=true
-        shift
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
+        if [ -n "$optValue" ]
+        then
+            replaceEtc  bashrc  \
+                WM_COMPILER_TYPE system \
+                WM_COMPILER "$optValue"
+            replaceEtcCsh  cshrc \
+                WM_COMPILER_TYPE system \
+                WM_COMPILER "$optValue"
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -third-compiler | -third | -ThirdParty)
        # Replace WM_COMPILER_TYPE=... and WM_COMPILER=...
-        optionValue=$(getOptionValue "$@")
-        replaceEtc  bashrc  \
-            WM_COMPILER_TYPE ThirdParty \
-            WM_COMPILER "$optionValue"
-        replaceEtcCsh  cshrc  \
-            WM_COMPILER_TYPE ThirdParty \
-            WM_COMPILER "$optionValue"
-        adjusted=true
-        shift
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
+        if [ -n "$optValue" ]
+        then
+            replaceEtc  bashrc  \
+                WM_COMPILER_TYPE ThirdParty \
+                WM_COMPILER "$optValue"
+            replaceEtcCsh  cshrc  \
+                WM_COMPILER_TYPE ThirdParty \
+                WM_COMPILER "$optValue"
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    gmp-[4-9]* | gmp-system)
        # gcc-related package
-        replaceEtc  config.sh/compiler   default_gmp_version "$1"
-        replaceEtc  config.csh/compiler  default_gmp_version "$1"
+        optValue="${1#-}"
+        replaceEtc  config.sh/compiler   default_gmp_version "$optValue"
+        replaceEtc  config.csh/compiler  default_gmp_version "$optValue"
        adjusted=true
        ;;

    mpfr-[2-9]* | mpfr-system)
        # gcc-related package
-        replaceEtc  config.sh/compiler   default_mpfr_version "$1"
-        replaceEtc  config.csh/compiler  default_mpfr_version "$1"
+        optValue="${1#-}"
+        replaceEtc  config.sh/compiler   default_mpfr_version "$optValue"
+        replaceEtc  config.csh/compiler  default_mpfr_version "$optValue"
        adjusted=true
        ;;

    mpc-[0-9]* | mpc-system)
        # gcc-related package
-        replaceEtc  config.sh/compiler   default_mpc_version "$1"
-        replaceEtc  config.csh/compiler  default_mpc_version "$1"
+        optValue="${1#-}"
+        replaceEtc  config.sh/compiler   default_mpc_version "$optValue"
+        replaceEtc  config.csh/compiler  default_mpc_version "$optValue"
        adjusted=true
        ;;


 ## MPI ##

-    -mpi)
+    -mpi=* | -mpi)
        # Explicitly set WM_MPLIB=...
-        optionValue=$(getOptionValue "$@")
-        replaceEtc     bashrc  WM_MPLIB "$optionValue"
-        replaceEtcCsh  cshrc   WM_MPLIB "$optionValue"
-        optMpi=system
-        adjusted=true
-        shift
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
+        if [ -n "$optValue" ]
+        then
+            replaceEtc     bashrc  WM_MPLIB "$optValue"
+            replaceEtcCsh  cshrc   WM_MPLIB "$optValue"
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

-    -openmpi)
-        # Replace FOAM_MPI=openmpi-<digits>.. and set to use third-party
-        #  The edit is slightly fragile, but works
-        expected="openmpi-[1-9][.0-9]*"
-        optMpi=$(getOptionValue "$@")
-
-        _matches "$optMpi" "$expected" || \
-            die "'$1' has bad value: '$optMpi'"
-
-        _inlineSed  $(_foamEtc config.sh/mpi) \
-            "FOAM_MPI=$expected" \
-            "FOAM_MPI=$optMpi" \
-            "Replaced 'FOAM_MPI=$expected' by 'FOAM_MPI=$optMpi'"
-
-        _inlineSed  $(_foamEtc config.csh/mpi) \
-            "FOAM_MPI $expected" \
-            "FOAM_MPI $optMpi" \
-            "Replaced 'FOAM_MPI $expected' by 'FOAM_MPI $optMpi'"
-
-        replaceEtc     bashrc  WM_MPLIB OPENMPI
-        replaceEtcCsh  cshrc   WM_MPLIB OPENMPI
-        adjusted=true
-        shift
-        ;;
-
-    -openmpi-system)
+    -sys-openmpi=* | -sys-openmpi | -openmpi-system)
+        optValue="$(echo "$1" | sed -ne 's/^.*mpi=\([1-9][0-9]*\).*/\1/p')"
        # Explicitly set WM_MPLIB=SYSTEMOPENMPI
-        replaceEtc     bashrc  WM_MPLIB SYSTEMOPENMPI
-        replaceEtcCsh  cshrc   WM_MPLIB SYSTEMOPENMPI
-        optMpi=system
-        adjusted=true
+        if [ -n "$optValue" ]
+        then
+            replaceEtc     bashrc  WM_MPLIB SYSTEMOPENMPI"$optValue"
+            replaceEtcCsh  cshrc   WM_MPLIB SYSTEMOPENMPI"$optValue"
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

-    -openmpi-third)
-        # Explicitly set WM_MPLIB=OPENMPI, using default setting for openmpi
+    -openmpi=* | -openmpi | -openmpi-third)
+        # Explicitly set WM_MPLIB=OPENMPI
+        # - use default setting for openmpi, or
+        #  replace FOAM_MPI=openmpi-<digits>..
+        #  The edit is slightly fragile, but works
+
+        expected="openmpi-[1-9][.0-9]*"
+        optValue="$(echo "$1" | sed -ne 's/^.*mpi=//p')"
+        if [ -n "$optValue" ]
+        then
+             if [ "${optValue#openmpi-}" = "$optValue" ]
+             then
+                 optValue="openmpi-$optValue"
+             fi
+
+            _matches "$optValue" "$expected" || \
+                die "'${1%=*}' has bad value: '$optValue'"
+
+            _inlineSed  "$(_foamEtc config.sh/mpi)" \
+                "FOAM_MPI=$expected" \
+                "FOAM_MPI=$optValue" \
+                "Replaced 'FOAM_MPI=$expected' by 'FOAM_MPI=$optValue'"
+
+            _inlineSed  "$(_foamEtc config.csh/mpi)" \
+                "FOAM_MPI=$expected" \
+                "FOAM_MPI=$optValue" \
+                "Replaced 'FOAM_MPI $expected' by 'FOAM_MPI $optValue'"
+        fi
        replaceEtc     bashrc  WM_MPLIB OPENMPI
        replaceEtcCsh  cshrc   WM_MPLIB OPENMPI
-        optMpi=third
        adjusted=true
        ;;

@ -599,146 +661,242 @@ CONFIG_CSH

    -adios | -adios2)
        # Replace adios2_version=...
-        optionValue=$(getOptionValue "$@")
-        replaceEtc  config.sh/adios2   adios2_version "$optionValue"
-        replaceEtc  config.csh/adios2  adios2_version "$optionValue"
-        adjusted=true
-        shift
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
+        if [ -n "$optValue" ]
+        then
+            replaceEtc  config.sh/adios2   adios2_version "$optValue"
+            replaceEtc  config.csh/adios2  adios2_version "$optValue"
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -adios-path | -adios2-path)
        # Replace ADIOS2_ARCH_PATH=...
-        optionValue=$(getOptionValue "$@")
-        replaceEtc     config.sh/adios2   ADIOS2_ARCH_PATH "\"$optionValue\""
-        replaceEtcCsh  config.csh/adios2  ADIOS2_ARCH_PATH "\"$optionValue\""
-        adjusted=true
-        shift
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
+        if [ -n "$optValue" ]
+        then
+            replaceEtc     config.sh/adios2   ADIOS2_ARCH_PATH "\"$optValue\""
+            replaceEtcCsh  config.csh/adios2  ADIOS2_ARCH_PATH "\"$optValue\""
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -boost)
        # Replace boost_version=...  (config is cgal or CGAL)
-        optionValue=$(getOptionValue "$@")
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
        cfgName=cgal; _foamEtc -q config.sh/"$cfgName" || cfgName=CGAL
-        replaceEtc  config.sh/"$cfgName"   boost_version "$optionValue"
-        replaceEtc  config.csh/"$cfgName"  boost_version "$optionValue"
-        adjusted=true
-        shift
+        if [ -n "$optValue" ]
+        then
+            replaceEtc  config.sh/"$cfgName"   boost_version "$optValue"
+            replaceEtc  config.csh/"$cfgName"  boost_version "$optValue"
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -boost-path)
        # Replace BOOST_ARCH_PATH=...  (config is cgal or CGAL)
-        optionValue=$(getOptionValue "$@")
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
        cfgName=cgal; _foamEtc -q config.sh/"$cfgName" || cfgName=CGAL
-        replaceEtc  config.sh/"$cfgName"   BOOST_ARCH_PATH "\"$optionValue\""
-        replaceEtc  config.csh/"$cfgName"  BOOST_ARCH_PATH "\"$optionValue\""
-        adjusted=true
-        shift
+        if [ -n "$optValue" ]
+        then
+            replaceEtc  config.sh/"$cfgName"   BOOST_ARCH_PATH "\"$optValue\""
+            replaceEtc  config.csh/"$cfgName"  BOOST_ARCH_PATH "\"$optValue\""
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -cgal)
        # Replace cgal_version=...  (config is cgal or CGAL)
-        optionValue=$(getOptionValue "$@")
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
        cfgName=cgal; _foamEtc -q config.sh/"$cfgName" || cfgName=CGAL
-        replaceEtc  config.sh/"$cfgName"   cgal_version "$optionValue"
-        replaceEtc  config.csh/"$cfgName"  cgal_version "$optionValue"
-        adjusted=true
-        shift
+        if [ -n "$optValue" ]
+        then
+            replaceEtc  config.sh/"$cfgName"   cgal_version "$optValue"
+            replaceEtc  config.csh/"$cfgName"  cgal_version "$optValue"
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -cgal-path)
        # Replace CGAL_ARCH_PATH=...  (config is cgal or CGAL)
-        optionValue=$(getOptionValue "$@")
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
        cfgName=cgal; _foamEtc -q config.sh/"$cfgName" || cfgName=CGAL
-        replaceEtc     config.sh/"$cfgName"   CGAL_ARCH_PATH "$optionValue"
-        replaceEtcCsh  config.csh/"$cfgName"  CGAL_ARCH_PATH "$optionValue"
-        adjusted=true
-        shift
+        if [ -n "$optValue" ]
+        then
+            replaceEtc     config.sh/"$cfgName"   CGAL_ARCH_PATH "$optValue"
+            replaceEtcCsh  config.csh/"$cfgName"  CGAL_ARCH_PATH "$optValue"
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -fftw)
        # Replace fftw_version=...
-        optionValue=$(getOptionValue "$@")
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
        # config.sh/fftw or config.sh/FFTW
        cfgName=fftw; _foamEtc -q config.sh/"$cfgName" || cfgName=FFTW
-        replaceEtc  config.sh/"$cfgName"   fftw_version "$optionValue"
-        replaceEtc  config.csh/"$cfgName"  fftw_version "$optionValue"
-        adjusted=true
-        shift
+        if [ -n "$optValue" ]
+        then
+            replaceEtc  config.sh/"$cfgName"   fftw_version "$optValue"
+            replaceEtc  config.csh/"$cfgName"  fftw_version "$optValue"
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -fftw-path)
        # Replace FFTW_ARCH_PATH=...
-        optionValue=$(getOptionValue "$@")
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
        # config.sh/fftw or config.sh/FFTW
        cfgName=fftw; _foamEtc -q config.sh/"$cfgName" || cfgName=FFTW
-        replaceEtc     config.sh/"$cfgName"  FFTW_ARCH_PATH "\"$optionValue\""
-        replaceEtcCsh  config.csh/"$cfgName" FFTW_ARCH_PATH "\"$optionValue\""
-        adjusted=true
-        shift
+        if [ -n "$optValue" ]
+        then
+            replaceEtc     config.sh/"$cfgName"  FFTW_ARCH_PATH "\"$optValue\""
+            replaceEtcCsh  config.csh/"$cfgName" FFTW_ARCH_PATH "\"$optValue\""
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -cmake)
        # Replace cmake_version=...
-        optionValue=$(getOptionValue "$@")
-        replaceEtc  config.sh/cmake   cmake_version "$optionValue"
-        adjusted=true
-        shift
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
+        if [ -n "$optValue" ]
+        then
+            replaceEtc  config.sh/cmake   cmake_version "$optValue"
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -cmake-path)
        # Replace CMAKE_ARCH_PATH=...
-        optionValue=$(getOptionValue "$@")
-        replaceEtc  config.sh/cmake   CMAKE_ARCH_PATH "$optionValue"
-        adjusted=true
-        shift
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
+        if [ -n "$optValue" ]
+        then
+            replaceEtc  config.sh/cmake   CMAKE_ARCH_PATH "$optValue"
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -kahip)
        # Replace KAHIP_VERSION=...
-        optionValue=$(getOptionValue "$@")
-        replaceEtc  config.sh/kahip  KAHIP_VERSION "$optionValue"
-        adjusted=true
-        shift
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
+        if [ -n "$optValue" ]
+        then
+            replaceEtc  config.sh/kahip  KAHIP_VERSION "$optValue"
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -kahip-path)
        # Replace KAHIP_ARCH_PATH=...
-        optionValue=$(getOptionValue "$@")
-        replaceEtc  config.sh/kahip  KAHIP_ARCH_PATH "\"$optionValue\""
-        adjusted=true
-        shift
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
+        if [ -n "$optValue" ]
+        then
+            replaceEtc  config.sh/kahip  KAHIP_ARCH_PATH "\"$optValue\""
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -metis)
        # Replace METIS_VERSION=...
-        optionValue=$(getOptionValue "$@")
-        replaceEtc  config.sh/metis  METIS_VERSION "$optionValue"
-        adjusted=true
-        shift
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
+        if [ -n "$optValue" ]
+        then
+            replaceEtc  config.sh/metis  METIS_VERSION "$optValue"
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -metis-path)
        # Replace METIS_ARCH_PATH=...
-        optionValue=$(getOptionValue "$@")
-        replaceEtc  config.sh/metis  METIS_ARCH_PATH "\"$optionValue\""
-        adjusted=true
-        shift
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
+        if [ -n "$optValue" ]
+        then
+            replaceEtc  config.sh/metis  METIS_ARCH_PATH "\"$optValue\""
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -scotch | -scotchVersion | --scotchVersion)
        # Replace SCOTCH_VERSION=...
-        optionValue=$(getOptionValue "$@")
-        replaceEtc  config.sh/scotch  SCOTCH_VERSION "$optionValue"
-        adjusted=true
-        shift
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
+        if [ -n "$optValue" ]
+        then
+            replaceEtc  config.sh/scotch  SCOTCH_VERSION "$optValue"
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -scotch-path | -scotchArchPath | --scotchArchPath)
        # Replace SCOTCH_ARCH_PATH=...
-        optionValue=$(getOptionValue "$@")
-        replaceEtc  config.sh/scotch  SCOTCH_ARCH_PATH "\"$optionValue\""
-        adjusted=true
-        shift
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
+        if [ -n "$optValue" ]
+        then
+            replaceEtc  config.sh/scotch  SCOTCH_ARCH_PATH "\"$optValue\""
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;


@ -747,107 +905,156 @@ CONFIG_CSH
    -paraview | -paraviewVersion | --paraviewVersion)
        # Replace ParaView_VERSION=...
        expected="[5-9][.0-9]*"  # but also accept system
-        optionValue=$(getOptionValue "$@")
-        _matches "$optionValue" "$expected" || \
-            [ "$optionValue" != "${optionValue%system}" ] || \
-            die "'$1' has bad value: '$optionValue'"
-        replaceEtc  config.sh/paraview   ParaView_VERSION "$optionValue"
-        replaceEtc  config.csh/paraview  ParaView_VERSION "$optionValue"
-        adjusted=true
-        shift
+        getOptionValue "$@"
+        _matches "$optValue" "$expected" || \
+            [ "$optValue" != "${optValue%system}" ] || \
+            die "'${1%=*}' has bad value: '$optValue'"
+
+        shift "${nOptArgs:-0}"
+        if [ -n "$optValue" ]
+        then
+            replaceEtc  config.sh/paraview   ParaView_VERSION "$optValue"
+            replaceEtc  config.csh/paraview  ParaView_VERSION "$optValue"
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -paraview-qt)
        # Replace ParaView_QT=...
-        optionValue=$(getOptionValue "$@")
-        replaceEtc  config.sh/paraview   ParaView_QT "$optionValue"
-        replaceEtc  config.csh/paraview  ParaView_QT "$optionValue"
-        adjusted=true
-        shift
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
+        if [ -n "$optValue" ]
+        then
+            replaceEtc  config.sh/paraview   ParaView_QT "$optValue"
+            replaceEtc  config.csh/paraview  ParaView_QT "$optValue"
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -paraview-path | -paraviewInstall | --paraviewInstall)
        # Replace ParaView_DIR=...
-        optionValue=$(getOptionValue "$@")
-        replaceEtc     config.sh/paraview   ParaView_DIR \""$optionValue\""
-        replaceEtcCsh  config.csh/paraview  ParaView_DIR \""$optionValue\""
-        adjusted=true
-        shift
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
+        if [ -n "$optValue" ]
+        then
+            replaceEtc     config.sh/paraview   ParaView_DIR \""$optValue\""
+            replaceEtcCsh  config.csh/paraview  ParaView_DIR \""$optValue\""
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -llvm)
        # Replace mesa_llvm=...
-        optionValue=$(getOptionValue "$@")
-        replaceEtc  config.sh/vtk   mesa_llvm "$optionValue"
-        replaceEtc  config.csh/vtk  mesa_llvm "$optionValue"
-        adjusted=true
-        shift
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
+        if [ -n "$optValue" ]
+        then
+            replaceEtc  config.sh/vtk   mesa_llvm "$optValue"
+            replaceEtc  config.csh/vtk  mesa_llvm "$optValue"
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -mesa)
        # Replace mesa_version=...
-        optionValue=$(getOptionValue "$@")
-        replaceEtc  config.sh/vtk   mesa_version "$optionValue"
-        replaceEtc  config.csh/vtk  mesa_version "$optionValue"
-        adjusted=true
-        shift
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
+        if [ -n "$optValue" ]
+        then
+            replaceEtc  config.sh/vtk   mesa_version "$optValue"
+            replaceEtc  config.csh/vtk  mesa_version "$optValue"
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -vtk)
        # Replace vtk_version=...
-        optionValue=$(getOptionValue "$@")
-        replaceEtc  config.sh/vtk   vtk_version "$optionValue"
-        replaceEtc  config.csh/vtk  vtk_version "$optionValue"
-        adjusted=true
-        shift
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
+        if [ -n "$optValue" ]
+        then
+            replaceEtc  config.sh/vtk   vtk_version "$optValue"
+            replaceEtc  config.csh/vtk  vtk_version "$optValue"
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -llvm-path)
        # Replace LLVM_ARCH_PATH=...
-        optionValue=$(getOptionValue "$@")
-        replaceEtc     config.sh/vtk   LLVM_ARCH_PATH \""$optionValue\""
-        replaceEtcCsh  config.csh/vtk  LLVM_ARCH_PATH \""$optionValue\""
-        adjusted=true
-        shift
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
+        if [ -n "$optValue" ]
+        then
+            replaceEtc     config.sh/vtk   LLVM_ARCH_PATH \""$optValue\""
+            replaceEtcCsh  config.csh/vtk  LLVM_ARCH_PATH \""$optValue\""
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -mesa-path)
        # Replace MESA_ARCH_PATH...
-        optionValue=$(getOptionValue "$@")
-        replaceEtc     config.sh/vtk   MESA_ARCH_PATH \""$optionValue\""
-        replaceEtcCsh  config.csh/vtk  MESA_ARCH_PATH \""$optionValue\""
-        adjusted=true
-        shift
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
+        if [ -n "$optValue" ]
+        then
+            replaceEtc     config.sh/vtk   MESA_ARCH_PATH \""$optValue\""
+            replaceEtcCsh  config.csh/vtk  MESA_ARCH_PATH \""$optValue\""
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;

    -vtk-path)
        # Replace VTK_DIR...
-        optionValue=$(getOptionValue "$@")
-        replaceEtc     config.sh/vtk   VTK_DIR \""$optionValue\""
-        replaceEtcCsh  config.csh/vtk  VTK_DIR \""$optionValue\""
-        adjusted=true
-        shift
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
+
+        if [ -n "$optValue" ]
+        then
+            replaceEtc     config.sh/vtk   VTK_DIR \""$optValue\""
+            replaceEtcCsh  config.csh/vtk  VTK_DIR \""$optValue\""
+            adjusted=true
+        else
+            : "${adjusted:=empty}"
+        fi
        ;;


 ## Misc ##

+    # Obsolete flags
    -sigfpe | -no-sigfpe)
        echo "Enable/disable FOAM_SIGFPE now via controlDict" 1>&2
        ;;

-    -archOption | --archOption)
-        # Replace WM_ARCH_OPTION=...
-        optionValue=$(getOptionValue "$@")
-        echo "Ignoring $1 option: no longer supported" 1>&2
-        shift
-        ;;
-
+    # Obsolete options
+    -archOption | --archOption | \
    -foamInstall | --foamInstall | -projectName | --projectName)
-        # Removed for 1812
-        optionValue=$(getOptionValue "$@")
-        echo "Ignoring $1 option: obsolete" 1>&2
-        shift
+        echo "Ignoring obsolete option: $1" 1>&2
+        getOptionValue "$@"
+        shift "${nOptArgs:-0}"
        ;;

    *)
--- a/etc/config.csh/paraview
+++ b/etc/config.csh/paraview
@ -99,7 +99,7 @@ case "none":
    breaksw

 case "system":
-    # Obtain major.minor from `paraview --version`
+    # Obtain (major.minor) from `paraview --version`
    set pv_api=`paraview --version | sed -ne 's/^[^0-9]*\([0-9][0-9]*\.[0-9][0-9]*\).*$/\1/p'`

    if ("${pv_api}" == "") then
@ -156,6 +156,7 @@ default:
    if ( -r "$ParaView_DIR" ) then
        setenv PATH "${ParaView_DIR}/bin:${PATH}"
        set pvLibDir="unknown"
+        set pv_libdirs=""

        # QT libraries as required, and Qt5_DIR for the root directory.
        # Another possibility: "qtpaths --qt-version"
@ -168,7 +169,7 @@ default:
            endsw
            foreach libDir ("lib$WM_COMPILER_LIB_ARCH" "lib")
                if ( -d "${qtDir}/${libDir}" ) then
-                    setenv LD_LIBRARY_PATH "${qtDir}/${libDir}:${LD_LIBRARY_PATH}"
+                    set pv_libdirs="${qtDir}/${libDir}"
                    break
                endif
            end
@ -182,11 +183,11 @@ default:
            set pvLibDir="${libDir}/paraview-${pv_api}"
            if ( -d "${ParaView_DIR}/${pvLibDir}" ) then
                switch ("$pv_api")
-                case 5.[0-4]*:
+                case 5.[0-4]:
                    set libDir="$pvLibDir"   # Needs lib/paraview-X.X (not lib)
                    breaksw
                endsw
-                setenv LD_LIBRARY_PATH "${ParaView_DIR}/${libDir}:${LD_LIBRARY_PATH}"
+                set pv_libdirs="${ParaView_DIR}/${libDir}:${pv_libdirs}"
                break
            endif
            set pvLibDir="unknown"
@ -200,6 +201,18 @@ default:
            set pv_plugin_dir="${pv_plugin_dir} (missing)"  # For message
        endif

+        # Any extra library directories
+        if ( "$pv_libdirs" != "" ) then
+            switch ("$WM_ARCH")
+            case darwin*:
+                setenv DYLD_LIBRARY_PATH "${pv_libdirs}:$DYLD_LIBRARY_PATH"
+                breaksw
+            default:
+                setenv LD_LIBRARY_PATH "${pv_libdirs}:$LD_LIBRARY_PATH"
+                breaksw
+            endsw
+        endif
+
        if ($?FOAM_VERBOSE && $?prompt) then
            echo "Using paraview"
            echo "    ParaView_DIR    : $ParaView_DIR"
@ -225,6 +238,6 @@ endif
 unsetenv ParaView_VERSION ParaView_QT

 unset archDir libDir
-unset pv_api pv_plugin_dir pvLibDir pvPython qtDir
+unset pv_api pv_plugin_dir pv_libdirs pvLibDir pvPython qtDir

 #------------------------------------------------------------------------------
--- a/etc/config.csh/settings
+++ b/etc/config.csh/settings
@ -82,11 +82,13 @@ case Linux:
    endsw
    breaksw

-# Presume x86_64, with clang (not gcc) as system compiler
+# arm64 or x86_64 architectures
 case Darwin:
    setenv WM_ARCH darwin64
-    if ( "$WM_COMPILER" == Gcc ) setenv WM_COMPILER Clang
-    echo "openfoam: darwin support is clang/llvm only"
+    if ( "$WM_COMPILER" == Gcc ) then
+        setenv WM_COMPILER Clang
+        echo "openfoam (darwin): using clang instead of gcc"
+    endif
    breaksw

 # Presume x86_64, with mingw cross-compiled
@ -96,7 +98,7 @@ case MSYS*:
    if ( "$WM_COMPILER" == Gcc ) setenv WM_COMPILER Mingw
    setenv WM_COMPILER_LIB_ARCH 64  # Consistent with linux64Mingw
    echo "openfoam: windows support (mingw64) is runtime only"
-    ;;
+    breaksw

 case SunOS*:
    setenv WM_ARCH solaris64
@ -146,12 +148,12 @@ setenv FOAM_USER_APPBIN "$WM_PROJECT_USER_DIR/platforms/$WM_OPTIONS/bin"
 setenv FOAM_USER_LIBBIN "$WM_PROJECT_USER_DIR/platforms/$WM_OPTIONS/lib"

 # Prepend wmake to the path - not required for runtime-only environment
-set foundDir="${WM_PROJECT_DIR}/wmake"
+set _foamFoundDir="${WM_PROJECT_DIR}/wmake"
 if ( $?WM_DIR ) then
-    if ( -d "${WM_DIR}" ) set foundDir="${WM_DIR}"
+    if ( -d "${WM_DIR}" ) set _foamFoundDir="${WM_DIR}"
 endif
-if ( -d "$foundDir" ) then
-    setenv PATH "${foundDir}:${PATH}"
+if ( -d "$_foamFoundDir" ) then
+    setenv PATH "${_foamFoundDir}:${PATH}"
 else
    unsetenv WM_DIR
 endif
@ -321,7 +323,7 @@ endsw

 # Cleanup
 # ~~~~~~~
-unset archDir siteDir foundDir archOption
+unset archOption archDir siteDir _foamFoundDir
 unset gcc_version gccDir
 unset gmp_version gmpDir  mpfr_version mpfrDir  mpc_version mpcDir
 unset clang_version clangDir
--- a/etc/config.csh/unset
+++ b/etc/config.csh/unset
@ -6,7 +6,7 @@
 #    \\/     M anipulation  |
 #------------------------------------------------------------------------------
 #     Copyright (C) 2011-2016 OpenFOAM Foundation
-#     Copyright (C) 2016-2020 OpenCFD Ltd.
+#     Copyright (C) 2016-2021 OpenCFD Ltd.
 #------------------------------------------------------------------------------
 # License
 #     This file is part of OpenFOAM, distributed under GPL-3.0-or-later.
@ -106,6 +106,11 @@ unsetenv FOAM_USER_APPBIN
 unsetenv FOAM_USER_LIBBIN
 unsetenv FOAM_UTILITIES

+# Build related
+unsetenv FOAM_BUILDROOT
+unsetenv FOAM_THIRD_PARTY_BUILDROOT
+unsetenv FOAM_THIRD_PARTY_SOURCES
+
 # Older, unused variables

 # Before 1812
@ -116,7 +121,14 @@ unsetenv FOAM_INST_DIR

 unsetenv MPI_ARCH_PATH
 unsetenv MPI_BUFFER_SIZE
-unsetenv OPAL_PREFIX
+
+# Cleanup mpi prefix values if set to one of the paths on foamOldDirs
+if ( $?foamClean ) then
+    # openmpi:
+    if ( "`$foamClean -env=OPAL_PREFIX $foamOldDirs`" == "" ) unsetenv OPAL_PREFIX
+    # intelmpi:
+    if ( "`$foamClean -env=I_MPI_ROOT $foamOldDirs`" == "" ) unsetenv I_MPI_ROOT
+endif


 #------------------------------------------------------------------------------
@ -153,21 +165,30 @@ unsetenv SCOTCH_ARCH_PATH
 # PATH, LD_LIBRARY_PATH, MANPATH

 if ( $?foamClean ) then
-
    eval `$foamClean -csh-env=PATH "$foamOldDirs"`
-
-    if ($?LD_LIBRARY_PATH) then
-        eval `$foamClean -csh-env=LD_LIBRARY_PATH "$foamOldDirs"`
-        if ("${LD_LIBRARY_PATH}" == "") unsetenv LD_LIBRARY_PATH
-    endif
-
    if ($?MANPATH) then
        eval `$foamClean -csh-env=MANPATH "$foamOldDirs"`
-        if ("${MANPATH}" == "") unsetenv MANPATH
    endif
-
+    if ($?LD_LIBRARY_PATH) then
+        eval `$foamClean -csh-env=LD_LIBRARY_PATH "$foamOldDirs"`
+    endif
+    if ($?DYLD_LIBRARY_PATH) then
+        eval `$foamClean -csh-env=DYLD_LIBRARY_PATH "$foamOldDirs"`
+    endif
 endif

+if ($?MANPATH) then
+    if ("${MANPATH}" == "") unsetenv MANPATH
+endif
+if ($?LD_LIBRARY_PATH) then
+    if ("${LD_LIBRARY_PATH}" == "") unsetenv LD_LIBRARY_PATH
+endif
+if ($?DYLD_LIBRARY_PATH) then
+    if ("${DYLD_LIBRARY_PATH}" == "") unsetenv DYLD_LIBRARY_PATH
+endif
+
+# Remove any shadow env variables
+unsetenv FOAM_DYLD_LIBRARY_PATH

 #------------------------------------------------------------------------------
 # Cleanup aliases
@ -214,6 +235,6 @@ endif
 #------------------------------------------------------------------------------
 # Intermediate variables (do as last for a clean exit code)

-unset cleaned foamClean foamOldDirs
+unset cleaned foamClean foamOldDirs _foamFoundDir

 #------------------------------------------------------------------------------
--- a/etc/config.sh/paraview
+++ b/etc/config.sh/paraview
@ -118,7 +118,7 @@ case "$ParaView_VERSION" in
        ;;

    ([0-9]*)
-        # Extract API from VERSION
+        # Extract API (major.minor) from VERSION
        pv_api=$(echo "$ParaView_VERSION" | \
            sed -ne 's/^[^0-9]*\([0-9][0-9]*\.[0-9][0-9]*\).*$/\1/p')
        ;;
@ -131,6 +131,7 @@ case "$ParaView_VERSION" in
    if [ -r "$ParaView_DIR" ]
    then
        export PATH="$ParaView_DIR/bin:$PATH"
+        unset pv_libdirs

        # QT libraries as required, and Qt5_DIR for the root directory.
        # Another possibility: "qtpaths --qt-version"
@ -146,7 +147,7 @@ case "$ParaView_VERSION" in
            do
                if [ -d "$qtDir/$libDir" ]
                then
-                    export LD_LIBRARY_PATH="$qtDir/$libDir:$LD_LIBRARY_PATH"
+                    pv_libdirs="$qtDir/$libDir"
                    break
                fi
            done
@ -161,11 +162,11 @@ case "$ParaView_VERSION" in
            if [ -d "$ParaView_DIR/$pvLibDir" ]
            then
                case "$pv_api" in
-                (5.[0-4]*)
+                (5.[0-4])
                    libDir="$pvLibDir"   # Needs lib/paraview-X.X (not lib)
                    ;;
                esac
-                export LD_LIBRARY_PATH="$ParaView_DIR/$libDir:$LD_LIBRARY_PATH"
+                pv_libdirs="$ParaView_DIR/$libDir:${pv_libdirs}"
                break
            fi
            unset pvLibDir
@ -180,6 +181,16 @@ case "$ParaView_VERSION" in
            pv_plugin_dir="${pv_plugin_dir} (missing)"  # For message
        fi

+        # Any extra library directories
+        if [ -n "$pv_libdirs" ]
+        then
+            case "$WM_ARCH" in
+            (darwin*)
+                export DYLD_LIBRARY_PATH="${pv_libdirs}:$DYLD_LIBRARY_PATH" ;;
+            (*) export LD_LIBRARY_PATH="${pv_libdirs}:$LD_LIBRARY_PATH" ;;
+            esac
+        fi
+
        if [ -n "$FOAM_VERBOSE" ] && [ -n "$PS1" ]
        then
            echo "Using paraview" 1>&2
@ -208,6 +219,6 @@ then
 fi

 unset archDir libDir
-unset pv_api pv_plugin_dir pvLibDir pvPython qtDir
+unset pv_api pv_plugin_dir pv_libdirs pvLibDir pvPython qtDir

 #------------------------------------------------------------------------------
--- a/etc/config.sh/settings
+++ b/etc/config.sh/settings
@ -78,11 +78,15 @@ Linux)
    esac
    ;;

-# Presume x86_64, with clang (not gcc) as system compiler
+# arm64 or x86_64 architectures
 Darwin)
    WM_ARCH=darwin64
-    [ "$WM_COMPILER" = Gcc ] && WM_COMPILER=Clang
-    echo "openfoam: darwin support is clang/llvm only" 1>&2
+    # Defult to clang (not gcc) as system compiler
+    if [ "$WM_COMPILER" = Gcc ]
+    then
+        WM_COMPILER=Clang
+        echo "openfoam (darwin): using clang instead of gcc" 1>&2
+    fi
    ;;

 # Presume x86_64, with mingw cross-compiled
@ -143,14 +147,14 @@ export FOAM_USER_LIBBIN="$WM_PROJECT_USER_DIR/platforms/$WM_OPTIONS/lib"


 # Prepend wmake to the path - not required for runtime-only environment
-foundDir="$WM_PROJECT_DIR/wmake"
+_foamFoundDir="$WM_PROJECT_DIR/wmake"
 if [ -d "$WM_DIR" ]
 then
-    foundDir="${WM_DIR}"
+    _foamFoundDir="${WM_DIR}"
 fi
-if [ -d "$foundDir" ]
+if [ -d "$_foamFoundDir" ]
 then
-    PATH="$foundDir:$PATH"
+    PATH="$_foamFoundDir:$PATH"
 else
    unset WM_DIR
 fi
@ -264,7 +268,7 @@ GCC_NOT_FOUND
    if [ -n "$FOAM_VERBOSE" ] && [ -n "$PS1" ]
    then
        echo "Using ThirdParty compiler"
-        echo "    ${gccDir##*/}  (${gmpDir##*/}  $${mpfrDir##*/}  ${mpcDir##*/})"
+        echo "    ${gccDir##*/}  (${gmpDir##*/}  ${mpfrDir##*/}  ${mpcDir##*/})"
    fi
    ;;

@ -312,7 +316,7 @@ esac

 # Cleanup
 # ~~~~~~~
-unset archDir siteDir foundDir archOption
+unset archOption archDir siteDir _foamFoundDir
 unset gcc_version gccDir
 unset gmp_version gmpDir  mpfr_version mpfrDir  mpc_version mpcDir
 unset clang_version clangDir
--- a/etc/config.sh/unset
+++ b/etc/config.sh/unset
@ -6,7 +6,7 @@
 #    \\/     M anipulation  |
 #------------------------------------------------------------------------------
 #     Copyright (C) 2011-2016 OpenFOAM Foundation
-#     Copyright (C) 2016-2020 OpenCFD Ltd.
+#     Copyright (C) 2016-2021 OpenCFD Ltd.
 #------------------------------------------------------------------------------
 # License
 #     This file is part of OpenFOAM, distributed under GPL-3.0-or-later.
@ -95,6 +95,11 @@ unset FOAM_USER_APPBIN
 unset FOAM_USER_LIBBIN
 unset FOAM_UTILITIES

+# Build related
+unset FOAM_BUILDROOT
+unset FOAM_THIRD_PARTY_BUILDROOT
+unset FOAM_THIRD_PARTY_SOURCES
+
 # Older, unused variables

 # Before 1812
@ -106,10 +111,13 @@ unset FOAM_INST_DIR
 unset MPI_ARCH_PATH
 unset MPI_BUFFER_SIZE

-# Undefine OPAL_PREFIX if set to one of the paths on foamOldDirs
-if [ -n "$foamClean" ] && [ -z "$($foamClean -env=OPAL_PREFIX $foamOldDirs)" ]
+# Cleanup mpi prefix values if set to one of the paths on foamOldDirs
+if [ -n "$foamClean" ]
 then
-    unset OPAL_PREFIX
+    # openmpi:
+    [ -z "$($foamClean -env=OPAL_PREFIX $foamOldDirs)" ] && unset OPAL_PREFIX
+    # intelmpi:
+    [ -z "$($foamClean -env=I_MPI_ROOT $foamOldDirs)" ] && unset I_MPI_ROOT
 fi

 #------------------------------------------------------------------------------
@ -154,12 +162,17 @@ unset SCOTCH_ARCH_PATH
 if [ -n "$foamClean" ]
 then
    eval "$($foamClean -sh-env=PATH $foamOldDirs)"
-    eval "$($foamClean -sh-env=LD_LIBRARY_PATH $foamOldDirs)"
    eval "$($foamClean -sh-env=MANPATH $foamOldDirs)"
+    eval "$($foamClean -sh-env=LD_LIBRARY_PATH $foamOldDirs)"
+    eval "$($foamClean -sh-env=DYLD_LIBRARY_PATH $foamOldDirs)"
 fi

-[ -n "$LD_LIBRARY_PATH" ] || unset LD_LIBRARY_PATH
 [ -n "$MANPATH" ] || unset MANPATH
+[ -n "$LD_LIBRARY_PATH" ] || unset LD_LIBRARY_PATH
+[ -n "$DYLD_LIBRARY_PATH" ] || unset DYLD_LIBRARY_PATH
+
+# Remove any shadow env variables
+unset FOAM_DYLD_LIBRARY_PATH

 #------------------------------------------------------------------------------
 # Cleanup aliases and functions
@ -218,6 +231,6 @@ unset _of_complete_cache_
 #------------------------------------------------------------------------------
 # Intermediate variables (do as last for a clean exit code)

-unset cleaned foamClean foamOldDirs
+unset cleaned foamClean foamOldDirs _foamFoundDir

 #------------------------------------------------------------------------------
--- a/wmake/scripts/have_scotch
+++ b/wmake/scripts/have_scotch
@ -5,7 +5,7 @@
 #   \\  /    A nd           | www.openfoam.com
 #    \\/     M anipulation  |
 #------------------------------------------------------------------------------
-#     Copyright (C) 2018-2020 OpenCFD Ltd.
+#     Copyright (C) 2018-2021 OpenCFD Ltd.
 #------------------------------------------------------------------------------
 # License
 #     This file is part of OpenFOAM, distributed under GPL-3.0-or-later.
@ -70,6 +70,10 @@
 # when MPI_ARCH_PATH=/usr/lib64/openmpi
 # and mpicc --showme:compile -> -I/usr/include/openmpi-x86_64
 #
+# NB: for RedHat (8+) /usr/include/scotch.h is a wrapper that includes
+#    /usr/include/scotch-64.h  (LP64 mode)
+# or /usr/include/scotch-32.h  (ILP32 mode)
+# In either case, int is 32 bits
 #
 # openSUSE
 # --------
@ -90,7 +94,7 @@
 no_scotch()
 {
    unset HAVE_SCOTCH SCOTCH_ARCH_PATH SCOTCH_INC_DIR SCOTCH_LIB_DIR
-    unset SCOTCH_VERSION
+    unset SCOTCH_VERSION SCOTCH_LIBNAME_SUFFIX
    unset HAVE_PTSCOTCH PTSCOTCH_ARCH_PATH PTSCOTCH_INC_DIR PTSCOTCH_LIB_DIR
 }

@ -161,6 +165,36 @@ search_scotch()
        return 2
    }

+    # ----------------------------------
+    # Extract 'typedef int64_t SCOTCH_Num' etc from header file
+    # - ensure consistent size between OpenFOAM and scotch header
+    # - for some systems, scotch.h includes scotch-64.h (for example).
+
+    local label
+    for hdr in \
+        "$header" \
+        "${header%/*}"/scotch-64.h \
+        "${header%/*}"/scotch-32.h \
+    ;
+    do
+        if [ -f "$hdr" ]
+        then
+            label=$(sed -ne \
+                's/^.*typedef *\([^ ]*\) *SCOTCH_Num.*/\1/p' \
+                "$hdr")
+
+            if [ -n "$label" ]
+            then
+                header="$hdr"  # Appears successful
+                break
+            fi
+        fi
+    done
+    : "${label:=unknown}"  # Safety
+
+    # Transform (int32_t | int64_t) -> (int32 | int64)
+    case "$label" in (int32_t | int64_t) label="${label%_t}" ;; esac
+
    # Library
    [ -n "$library" ] \
    || library=$(findLibrary -prefix="$prefix" -name="$libName" -local="$localDir") \
@ -171,16 +205,6 @@ search_scotch()

    # ----------------------------------

-    local label
-
-    # Ensure consistent sizes between OpenFOAM and scotch header
-    # extract 'typedef int64_t SCOTCH_Num' or equivalent
-    label=$(sed -ne \
-        's/^.*typedef *\([^ ]*\) *SCOTCH_Num.*/\1/p' \
-        "$header")
-    : "${label:=unknown}"
-
-
    # No SCOTCH_VERSION set? Try to obtain from header
    # extract #define SCOTCH_VERSION, SCOTCH_RELEASE, SCOTCH_PATCHLEVEL
    [ -n "$SCOTCH_VERSION" ] || \
@ -198,7 +222,8 @@ search_scotch()
    : "${SCOTCH_VERSION:=scotch}"  # Failsafe value

    case "$WM_LABEL_SIZE:$label" in
-    (32:int32_t | 32:int | 64:int64_t | 64:long)
+    ( 32:int32 | 32:int \
+    | 64:int64 | 64:long )
        ;;

    (*)
@ -212,7 +237,7 @@ search_scotch()
    esac

    # OK
-    echo "scotch (label=$label) - $prefix"
+    echo "scotch ($label) - $prefix"
    export HAVE_SCOTCH=true
    export SCOTCH_ARCH_PATH="$prefix"
    export SCOTCH_INC_DIR="${header%/*}"     # Basename