Corrected co_broadcast argument size check (previous version was inadvertently hardwired to work only for the tested string length).

Author: Damian Rouson

src/libcaf-gfortran-descriptor.h

@@ -133,10 +133,9 @@ typedef struct gfc_descriptor_t {
     receives in the dtype component its gf_descriptor_t argument for character(kind=c_char) 
     and logical(kind=c_bool) data:
 */
-#define GFC_DTYPE_CHARACTER 944 
+#define GFC_DTYPE_CHARACTER 48
 
 #if 0
-#define GFC_DTYPE_LOGICAL_4 8
 #define GFC_DTYPE_CHARACTER ((BT_CHARACTER << GFC_DTYPE_TYPE_SHIFT) \
    | (sizeof(char) << GFC_DTYPE_SIZE_SHIFT))
 #endif

src/mpi/mpi_caf.c

@@ -1839,9 +1839,13 @@ get_MPI_datatype (gfc_descriptor_t *desc)
       return MPI_COMPLEX;
     case GFC_DTYPE_COMPLEX_8:
       return MPI_DOUBLE_COMPLEX;
-    case GFC_DTYPE_CHARACTER:
-      return MPI_CHARACTER;
     }
+/* gfortran passes character string arguments with a 
+   GFC_DTYPE_TYPE_SIZE == GFC_TYPE_CHARACTER + 64*strlen
+*/
+  if ( (GFC_DTYPE_TYPE_SIZE(desc)-GFC_DTYPE_CHARACTER)%64==0 )
+      return MPI_CHARACTER;
+
   caf_runtime_error ("Unsupported data type in collective: %ld\n",GFC_DTYPE_TYPE_SIZE (desc)); 
   return 0;
 }