diff --git a/ext/xmlreader/php_xmlreader.c b/ext/xmlreader/php_xmlreader.c
index c41429c5975..2c7c054b110 100644
--- a/ext/xmlreader/php_xmlreader.c
+++ b/ext/xmlreader/php_xmlreader.c
@@ -469,6 +469,7 @@ static void php_xmlreader_no_arg(INTERNAL_FUNCTION_PARAMETERS, xmlreader_read_in
 }
 /* }}} */
 
+#if LIBXML_VERSION >= 20620
 /* {{{ php_xmlreader_no_arg_string */
 static void php_xmlreader_no_arg_string(INTERNAL_FUNCTION_PARAMETERS, xmlreader_read_char_t internal_function) {
 	zval *id;
@@ -490,6 +491,7 @@ static void php_xmlreader_no_arg_string(INTERNAL_FUNCTION_PARAMETERS, xmlreader_
 	}
 }
 /* }}} */
+#endif
 
 /* {{{ php_xmlreader_set_relaxng_schema */
 static void php_xmlreader_set_relaxng_schema(INTERNAL_FUNCTION_PARAMETERS, int type) {