diff --git a/ext/filter/filter.c b/ext/filter/filter.c
index f84b001205c..08e01bdabe6 100644
--- a/ext/filter/filter.c
+++ b/ext/filter/filter.c
@@ -77,7 +77,7 @@ static const filter_list_entry filter_list[] = {
 #define PARSE_SESSION 6
 #endif
 
-static unsigned int php_sapi_filter(int arg, char *var, char **val, unsigned int val_len, unsigned int *new_val_len TSRMLS_DC);
+static unsigned int php_sapi_filter(int arg, char *var, char **val, php_size_t val_len, php_size_t *new_val_len TSRMLS_DC);
 static unsigned int php_sapi_filter_init(TSRMLS_D);
 
 /* {{{ arginfo */
@@ -402,7 +402,7 @@ static void php_zval_filter(zval *value, php_int_t filter, php_int_t flags, zval
 }
 /* }}} */
 
-static unsigned int php_sapi_filter(int arg, char *var, char **val, unsigned int val_len, unsigned int *new_val_len TSRMLS_DC) /* {{{ */
+static unsigned int php_sapi_filter(int arg, char *var, char **val, php_size_t val_len, php_size_t *new_val_len TSRMLS_DC) /* {{{ */
 {
 	zval  new_var, raw_var;
 	zval *array_ptr = NULL, *orig_array_ptr = NULL;