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This commit was SVN r22025.

ompi/datatype/ompi_datatype.h

@@ -201,8 +201,8 @@ ompi_datatype_duplicate( const ompi_datatype_t* oldType, ompi_datatype_t** newTy
         return OMPI_ERR_OUT_OF_RESOURCE;
     }
     opal_datatype_clone ( &oldType->super, &new_ompi_datatype->super);
-
-    new_ompi_datatype->super.flags &= (~OMPI_DATATYPE_FLAG_PREDEFINED);
+    /* Strip the predefined flag at the OMPI level. */
+    new_ompi_datatype->super.flags &= ~OMPI_DATATYPE_FLAG_PREDEFINED;
 
     /* Set the keyhash to NULL -- copying attributes is *only* done at
        the top level (specifically, MPI_TYPE_DUP). */