diff --git a/src/backend/catalog/index.c b/src/backend/catalog/index.c
index e9955707fa..79439a0c66 100644
--- a/src/backend/catalog/index.c
+++ b/src/backend/catalog/index.c
@@ -312,6 +312,14 @@ ConstructTupleDescriptor(Relation heapRelation,
 		to->attcollation = (i < numkeyatts) ?
 			collationObjectId[i] : InvalidOid;
 
+		/*
+		 * Set the attribute name as specified by caller.
+		 */
+		if (colnames_item == NULL)	/* shouldn't happen */
+			elog(ERROR, "too few entries in colnames list");
+		namestrcpy(&to->attname, (const char *) lfirst(colnames_item));
+		colnames_item = lnext(indexColNames, colnames_item);
+
 		/*
 		 * For simple index columns, we copy some pg_attribute fields from the
 		 * parent relation.  For expressions we have to look at the expression
@@ -329,7 +337,6 @@ ConstructTupleDescriptor(Relation heapRelation,
 			from = TupleDescAttr(heapTupDesc,
 								 AttrNumberGetAttrOffset(atnum));
 
-			namecpy(&to->attname, &from->attname);
 			to->atttypid = from->atttypid;
 			to->attlen = from->attlen;
 			to->attndims = from->attndims;
@@ -390,14 +397,6 @@ ConstructTupleDescriptor(Relation heapRelation,
 		 */
 		to->attrelid = InvalidOid;
 
-		/*
-		 * Set the attribute name as specified by caller.
-		 */
-		if (colnames_item == NULL)	/* shouldn't happen */
-			elog(ERROR, "too few entries in colnames list");
-		namestrcpy(&to->attname, (const char *) lfirst(colnames_item));
-		colnames_item = lnext(indexColNames, colnames_item);
-
 		/*
 		 * Check the opclass and index AM to see if either provides a keytype
 		 * (overriding the attribute type).  Opclass (if exists) takes