WIP: Use findMPI earlier.

Author: vehre

.github/workflows/win-ci.yml

@@ -46,8 +46,10 @@ jobs:
         # cat "${I_MPI_ROOT}/bin/mpifc.bat"
         # mpifc.bat -show
         # mpicc.bat -show
-        mpifc.bat -version || echo "ifort not installed"
-        mpicc.bat -version || echo "icc not installed"
+        export I_MPI_CC=gcc
+        export I_MPI_FC=gfortran
+        mpifc.bat --version || echo "ifort not installed"
+        mpicc.bat --version || echo "icc not installed"
         set +o verbose
         # echo The following environment variables are used:
         # echo    CMPLR_ROOT      Intel^(R^) Compiler installation directory path
@@ -62,6 +64,8 @@ jobs:
 
     - name: Build and Test
       run: |
+        export I_MPI_CC=gcc
+        export I_MPI_FC=gfortran
         mkdir build
         cmake -Wdev -G "Unix Makefiles" -S . -B build -DCMAKE_INSTALL_PREFIX="${HOME}/apps/OpenCoarrays" -DCMAKE_BUILD_TYPE:STRING="Debug"
         cmake --build build -j

CMakeLists.txt

@@ -282,7 +282,9 @@ if (C_COMPILER_NAME MATCHES "^[mM][pP][iI]")
   set (MPI_C_COMPILER "${CMAKE_C_COMPILER}")
 endif()
 
-if(WIN32) # Only support building with GCC & GFortran using Intel MPI (OneAPI)
+find_package(MPI)
+
+if(WIN32 AND NOT MPI_FOUND) # Only support building with GCC & GFortran using Intel MPI (OneAPI)
   # Here we assume Intel ONEAPI and the environment is loaded
   set( MPI_ASSUME_NO_BUILTIN_MPI TRUE )
   set( MPI_CXX_SKIP_MPICXX TRUE )
@@ -319,7 +321,6 @@ if(WIN32) # Only support building with GCC & GFortran using Intel MPI (OneAPI)
   set(MPI_Fortran_HAVE_F08_MODULE FALSE)
 
 endif()
-find_package( MPI )
 
 if ( (NOT MPI_C_FOUND) OR (NOT MPI_Fortran_FOUND) OR (NOT MPIEXEC_EXECUTABLE))
   # Get default install location of MPICH from install.sh
@@ -339,7 +340,7 @@ MPIEXEC_EXECUTABLE = ${MPIEXEC_EXECUTABLE}
     HINTS "${FTN_COMPILER_DIR}" "${C_COMPILER_DIR}"
     PATH_SUFFIXES bin)
   set ( MPI_HOME "${MPI_HOME}" "${MY_MPI_EXEC}" "${MY_MPI_EXEC}/.." )
-  find_package( MPI REQUIRED )
+#  find_package( MPI REQUIRED )
 endif()
 list(REMOVE_DUPLICATES MPI_Fortran_INCLUDE_DIRS)