Fortran: allow main in Fortran

GNUmakefile.in

@@ -1,4 +1,6 @@
 
+USE_AMREX_FI_MAIN = FALSE
+
 AMREX_HOME := $(shell pwd)
 
 include $(AMREX_HOME)/Tools/GNUMake/Make.defs

Src/Base/AMReX_ParallelDescriptor.cpp

@@ -43,6 +43,11 @@ extern "C" {
 #include <omp.h>
 #endif
 
+namespace
+{
+    static int call_mpi_finalize = 0;
+}
+
 namespace amrex {
 
 namespace ParallelDescriptor
@@ -288,6 +293,7 @@ ParallelDescriptor::StartParallel (int*    argc,
 
     if ( ! sflag) {
 	BL_MPI_REQUIRE( MPI_Init(argc, argv) );
+        call_mpi_finalize = 1;
     }
 
     BL_MPI_REQUIRE( MPI_Comm_dup(mpi_comm, &m_comm_all) );
@@ -343,7 +349,9 @@ ParallelDescriptor::EndParallel ()
     }
 #endif
 
-    BL_MPI_REQUIRE( MPI_Finalize() );
+    if (call_mpi_finalize) {
+        BL_MPI_REQUIRE( MPI_Finalize() );
+    }
 }
 
 /* Given `rk_clrd', i.e. the rank in the colored `comm', return the

Src/F_Interfaces/Base/AMReX_base_mod.F90

@@ -3,6 +3,8 @@ module amrex_base_module
 
   use iso_c_binding
 
+  use amrex_init_module
+
   use amrex_error_module
   use amrex_fort_module
   use amrex_box_module
@@ -25,13 +27,4 @@ module amrex_base_module
 
   use mempool_module
 
-contains
-
-  subroutine amrex_fi_init () bind(c)
-  end subroutine amrex_fi_init
-
-
-  subroutine amrex_fi_finalize () bind(c)
-  end subroutine amrex_fi_finalize
-
 end module amrex_base_module

Src/F_Interfaces/Base/AMReX_fi_main.cpp

@@ -3,24 +3,18 @@
 #include <AMReX_BLProfiler.H>
 
 extern "C" { 
-    void amrex_fi_init();
-    void amrex_fi_finalize();
     void amrex_fmain();
 }
 
 int main (int argc, char* argv[])
 {
     amrex::Initialize(argc,argv);
 
-    amrex_fi_init();
-
     BL_PROFILE_VAR("main()", pmain);
 
     amrex_fmain();
 
     BL_PROFILE_VAR_STOP(pmain);
 
-    amrex_fi_finalize();
-
     amrex::Finalize();
 }

Src/F_Interfaces/Base/Make.package

@@ -6,12 +6,15 @@ ifeq ($(USE_AMREX_FI_MAIN),TRUE)
   CEXE_sources += AMReX_fi_main.cpp
 endif
 
+F90EXE_sources += AMReX_init_mod.F90
+
 F90EXE_sources += AMReX_parallel_mod.F90
 
 F90EXE_sources += AMReX_base_mod.F90 AMReX_box_mod.F90 AMReX_boxarray_mod.F90 AMReX_distromap_mod.F90
 F90EXE_sources += AMReX_geometry_mod.F90 AMReX_multifab_mod.F90 AMReX_plotfile_mod.F90
 F90EXE_sources += AMReX_multifabutil_mod.F90 AMReX_physbc_mod.F90 AMReX_fab_mod.F90
 
+CEXE_sources += AMReX_init_fi.cpp
 CEXE_sources += AMReX_box_fi.cpp AMReX_boxarray_fi.cpp AMReX_distromap_fi.cpp AMReX_geometry_fi.cpp
 CEXE_sources += AMReX_multifab_fi.cpp AMReX_vismf_fi.cpp AMReX_plotfile_fi.cpp
 CEXE_sources += AMReX_multifabutil_fi.cpp AMReX_physbc_fi.cpp

Tutorials/Basic/main_F/GNUmakefile

@@ -0,0 +1,21 @@
+AMREX_HOME ?= ../../../
+
+DEBUG	= FALSE
+DEBUG	= TRUE
+
+DIM	= 3
+
+COMP    = gnu
+
+USE_MPI   = TRUE
+USE_OMP   = FALSE
+
+USE_AMREX_FI_MAIN = FALSE
+
+include $(AMREX_HOME)/Tools/GNUMake/Make.defs
+
+include ./Make.package
+include $(AMREX_HOME)/Src/Base/Make.package
+include $(AMREX_HOME)/Src/F_Interfaces/Base/Make.package
+
+include $(AMREX_HOME)/Tools/GNUMake/Make.rules

Tutorials/Basic/main_F/Make.package

@@ -0,0 +1 @@
+F90EXE_sources += main.F90

Tutorials/Basic/main_F/main.F90

@@ -0,0 +1,22 @@
+
+program main
+
+  use mpi
+  use amrex_base_module
+
+  implicit none
+
+  integer :: ierr
+
+  call mpi_init(ierr)
+
+  call amrex_init()
+
+
+
+
+  call amrex_finalize()
+
+  call mpi_finalize()
+
+end program main