diff --git a/wp-includes/class-IXR.php b/wp-includes/class-IXR.php
index 7d678fdf7..00f4a0eb8 100644
--- a/wp-includes/class-IXR.php
+++ b/wp-includes/class-IXR.php
@@ -556,6 +556,7 @@ class IXR_Client {
         }
         fputs($fp, $request);
         $contents = '';
+        $debug_contents = '';
         $gotFirstLine = false;
         $gettingHeaders = true;
         while (!feof($fp)) {