diff --git a/src/if_ruby.c b/src/if_ruby.c
index 41cb791..2ee329b 100644
--- a/src/if_ruby.c
+++ b/src/if_ruby.c
@@ -722,8 +722,8 @@
 
     if (tv->v_type == VAR_STRING)
     {
-	result = rb_str_new2((char *)(tv->vval.v_string == NULL
-						   ? "" : tv->vval.v_string));
+	result = rb_str_new2(tv->vval.v_string == NULL
+					  ? "" : (char *)(tv->vval.v_string));
     }
     else if (tv->v_type == VAR_NUMBER)
     {