diff --git src/wp-includes/ID3/module.audio-video.riff.php src/wp-includes/ID3/module.audio-video.riff.php
index e745ec65f4..77293423fb 100644
--- src/wp-includes/ID3/module.audio-video.riff.php
+++ src/wp-includes/ID3/module.audio-video.riff.php
@@ -1620,7 +1620,6 @@ class getid3_riff extends getid3_handler
 							if (!$FoundAllChunksWeNeed) {
 								$WhereWeWere      = $this->ftell();
 								$AudioChunkHeader = $this->fread(12);
-								$AudioChunkStreamNum  =                              substr($AudioChunkHeader, 0, 2);
 								$AudioChunkStreamType =                              substr($AudioChunkHeader, 2, 2);
 								$AudioChunkSize       = getid3_lib::LittleEndian2Int(substr($AudioChunkHeader, 4, 4));
 
diff --git src/wp-includes/class-wp-comment-query.php src/wp-includes/class-wp-comment-query.php
index dad512c419..91a4164e41 100644
--- src/wp-includes/class-wp-comment-query.php
+++ src/wp-includes/class-wp-comment-query.php
@@ -584,8 +584,6 @@ class WP_Comment_Query {
 		if ( ! empty( $this->query_vars['include_unapproved'] ) ) {
 			$include_unapproved = wp_parse_list( $this->query_vars['include_unapproved'] );
 
-			$unapproved_ids    = array();
-			$unapproved_emails = array();
 			foreach ( $include_unapproved as $unapproved_identifier ) {
 				// Numeric values are assumed to be user IDs.
 				if ( is_numeric( $unapproved_identifier ) ) {
diff --git src/wp-includes/rest-api/endpoints/class-wp-rest-revisions-controller.php src/wp-includes/rest-api/endpoints/class-wp-rest-revisions-controller.php
index 23f9ada215..e1f5384f0d 100644
--- src/wp-includes/rest-api/endpoints/class-wp-rest-revisions-controller.php
+++ src/wp-includes/rest-api/endpoints/class-wp-rest-revisions-controller.php
@@ -406,8 +406,6 @@ class WP_REST_Revisions_Controller extends WP_REST_Controller {
 			return $parent;
 		}
 
-		$parent_post_type = get_post_type_object( $parent->post_type );
-
 		if ( ! current_user_can( 'delete_post', $parent->ID ) ) {
 			return new WP_Error(
 				'rest_cannot_delete',