fixing some group function with respect to how to determine the rank of a process in the group.

This commit was SVN r2623.

src/mpi/c/group_difference.c

@@ -110,8 +110,22 @@ int MPI_Group_difference(MPI_Group group1, MPI_Group group2,
 
     /* find my rank */
     my_group_rank=group1_pointer->grp_my_rank;
-    my_proc_pointer=group1_pointer->grp_proc_pointers[my_group_rank];
-    ompi_set_group_rank(new_group_pointer,my_proc_pointer);
+    if ( MPI_UNDEFINED != my_group_rank ) {
+	my_proc_pointer=group1_pointer->grp_proc_pointers[my_group_rank];
+    }
+    else {
+	my_group_rank=group2_pointer->grp_my_rank;
+	if ( MPI_UNDEFINED != my_group_rank ) {
+	    my_proc_pointer=group2_pointer->grp_proc_pointers[my_group_rank];
+	}
+    }
+
+    if ( MPI_UNDEFINED == my_group_rank ) {
+	new_group_pointer->grp_my_rank = MPI_UNDEFINED;
+    }
+    else {
+	ompi_set_group_rank(new_group_pointer,my_proc_pointer);
+    }
 
     *new_group = (MPI_Group)new_group_pointer;
 

src/mpi/c/group_free.c

@@ -29,8 +29,7 @@ int MPI_Group_free(MPI_Group *group)
     if (MPI_PARAM_CHECK) {
         OMPI_ERR_INIT_FINALIZE(FUNC_NAME);
 
-        if ((MPI_GROUP_NULL == *group) || (MPI_GROUP_EMPTY == *group) ||
-                (NULL == *group) ) {
+        if ((MPI_GROUP_NULL == *group) || (NULL == *group) ) {
             return OMPI_ERRHANDLER_INVOKE(MPI_COMM_WORLD, MPI_ERR_GROUP,
                                           FUNC_NAME);
         }

src/mpi/c/group_intersection.c

@@ -99,8 +99,22 @@ int MPI_Group_intersection(MPI_Group group1, MPI_Group group2,
 
     /* find my rank */
     my_group_rank=group1_pointer->grp_my_rank;
-    my_proc_pointer=group1_pointer->grp_proc_pointers[my_group_rank];
-    ompi_set_group_rank(new_group_pointer,my_proc_pointer);
+    if ( MPI_UNDEFINED != my_group_rank ) {
+	my_proc_pointer=group1_pointer->grp_proc_pointers[my_group_rank];
+    }
+    else {
+	my_group_rank=group2_pointer->grp_my_rank;
+	if ( MPI_UNDEFINED != my_group_rank  ) {
+	    my_proc_pointer=group2_pointer->grp_proc_pointers[my_group_rank];
+	}
+    }
+
+    if ( MPI_UNDEFINED == my_group_rank ) {
+	new_group_pointer->grp_my_rank = MPI_UNDEFINED;
+    }
+    else {
+	ompi_set_group_rank(new_group_pointer,my_proc_pointer);
+    }
 
     *new_group = (MPI_Group)new_group_pointer;
 

src/mpi/c/group_union.c

@@ -125,12 +125,19 @@ int MPI_Group_union(MPI_Group group1, MPI_Group group2, MPI_Group *new_group)
     my_group_rank = group1_pointer->grp_my_rank;
     if (MPI_UNDEFINED == my_group_rank) {
         my_group_rank = group2_pointer->grp_my_rank;
-        my_proc_pointer = group2_pointer->grp_proc_pointers[my_group_rank];
+	if ( MPI_UNDEFINED != my_group_rank) {
+	    my_proc_pointer = group2_pointer->grp_proc_pointers[my_group_rank];
+	}
     } else {
         my_proc_pointer = group1_pointer->grp_proc_pointers[my_group_rank];
     }
 
-    ompi_set_group_rank(new_group_pointer, my_proc_pointer);
+    if ( MPI_UNDEFINED == my_group_rank ) {
+	new_group_pointer->grp_my_rank = MPI_UNDEFINED;
+    }
+    else {
+	ompi_set_group_rank(new_group_pointer, my_proc_pointer);
+    }
 
     *new_group = (MPI_Group) new_group_pointer;