diff --git a/Zend/zend_language_scanner.l b/Zend/zend_language_scanner.l
index 3ea51fe7c9d02..6276bd785b2e9 100644
--- a/Zend/zend_language_scanner.l
+++ b/Zend/zend_language_scanner.l
@@ -911,7 +911,7 @@ ZEND_API void zend_multibyte_yyinput_again(zend_encoding_filter old_input_filter
 		ZVAL_STRINGL(zendlval, yytext, yyleng); \
 	}
 
-static zend_result zend_scan_escape_string(zval *zendlval, char *str, int len, char quote_type)
+static zend_result zend_scan_escape_string(zval *zendlval, char *str, size_t len, char quote_type)
 {
 	char *s, *t;
 	char *end;