diff --git a/src/wp-includes/comment.php b/src/wp-includes/comment.php
index e69fe3a496..f265530ac6 100644
--- a/src/wp-includes/comment.php
+++ b/src/wp-includes/comment.php
@@ -443,8 +443,14 @@ class WP_Comment_Query {
 		 * @param WP_Comment_Query &$this  Current instance of WP_Comment_Query, passed by reference.
 		 */
 		$clauses = apply_filters_ref_array( 'comments_clauses', array( compact( $pieces ), &$this ) );
-		foreach ( $pieces as $piece )
-			$$piece = isset( $clauses[ $piece ] ) ? $clauses[ $piece ] : '';
+
+		$fields = isset( $clauses[ 'fields' ] ) ? $clauses[ 'fields' ] : '';
+		$join = isset( $clauses[ 'join' ] ) ? $clauses[ 'join' ] : '';
+		$where = isset( $clauses[ 'where' ] ) ? $clauses[ 'where' ] : '';
+		$orderby = isset( $clauses[ 'orderby' ] ) ? $clauses[ 'orderby' ] : '';
+		$order = isset( $clauses[ 'order' ] ) ? $clauses[ 'order' ] : '';
+		$limits = isset( $clauses[ 'limits' ] ) ? $clauses[ 'limits' ] : '';
+		$groupby = isset( $clauses[ 'groupby' ] ) ? $clauses[ 'groupby' ] : '';
 
 		if ( $groupby ) {
 			$groupby = 'GROUP BY ' . $groupby;