diff --git a/ext/standard/math.c b/ext/standard/math.c
index 2d0c8fc09e9..142d473864f 100644
--- a/ext/standard/math.c
+++ b/ext/standard/math.c
@@ -304,7 +304,7 @@ PHP_FUNCTION(floor)
 }
 /* }}} */
 
-int php_math_round_mode_from_enum(zend_object *mode)
+PHPAPI int php_math_round_mode_from_enum(zend_object *mode)
 {
 	zval *case_name = zend_enum_fetch_case_name(mode);
 	zend_string *mode_name = Z_STR_P(case_name);
diff --git a/ext/standard/php_math_round_mode.h b/ext/standard/php_math_round_mode.h
index 11a8e873204..e8cbec64066 100644
--- a/ext/standard/php_math_round_mode.h
+++ b/ext/standard/php_math_round_mode.h
@@ -52,4 +52,4 @@
 
 extern PHPAPI zend_class_entry *rounding_mode_ce;
 
-int php_math_round_mode_from_enum(zend_object *mode);
+PHPAPI int php_math_round_mode_from_enum(zend_object *mode);