diff --git a/parse.h b/parse.h
index 5273d23..1009252 100644
--- a/parse.h
+++ b/parse.h
@@ -100,7 +100,7 @@
 typedef int (fio_opt_int_fn)(void *, int *);
 typedef int (fio_opt_str_set_fn)(void *);
 
-#define __td_var(start, offset)	((void *) start + (offset))
+#define __td_var(start, offset)	((char *) start + (offset))
 
 struct thread_options;
 static inline void *td_var(struct thread_options *to, struct fio_option *o,