Index: src/wp-includes/option.php
===================================================================
--- src/wp-includes/option.php	(revision 33902)
+++ src/wp-includes/option.php	(working copy)
@@ -512,13 +512,14 @@
 	if ( ! defined( 'WP_INSTALLING' ) ) {
 		if ( 'yes' == $row->autoload ) {
 			$alloptions = wp_load_alloptions();
-			if ( is_array( $alloptions ) && isset( $alloptions[$option] ) ) {
+			if ( is_array( $alloptions ) && array_key_exists( $option, $alloptions ) ) {
 				unset( $alloptions[$option] );
 				wp_cache_set( 'alloptions', $alloptions, 'options' );
 			}
-		} else {
-			wp_cache_delete( $option, 'options' );
 		}
+
+		wp_cache_delete( $option, 'options' );
+
 	}
 	if ( $result ) {