Ticket #38082: 38082.0.diff

src/wp-includes/meta.php

@@ -463 +463 @@
                 return false;
         }
 
-        $object_id = absint( $object_id );
+        $object_id = intval( $object_id );
         if ( ! $object_id ) {
                 return false;
         }
@@ -476 +476 @@
          * will effectively short-circuit the function.
          *
          * @since 3.1.0
+         * @since 4.7.0 The $object_id may be negative when representing placeholder objects.
          *
          * @param null|array|string $value     The value get_metadata() should return - a single metadata value,
          *                                     or an array of values.
@@ -491 +492 @@
                         return $check;
         }
 
+        /*
+         * A negative ID is used to represent a placeholder object. Since such an ID
+         * could not exist in the DB where IDs are UNSIGNED INTEGERS then the function
+         * must short circuit here. Meta for placeholder objects must be supplied
+         * via the get_{$meta_type}_metadata filterl.
+         *
+         */
+        if ( $object_id < 0 ) {
+                return false;
+        }
+
         $meta_cache = wp_cache_get($object_id, $meta_type . '_meta');
 
         if ( !$meta_cache ) {