diff --git a/examples/bare4.rs b/examples/bare4.rs
index 9af31a0aeb035c6baf7ccce091ce3336b24fa090..a5850315f68cca5165ce3d82a8cf1272bdba68a4 100644
--- a/examples/bare4.rs
+++ b/examples/bare4.rs
@@ -121,7 +121,8 @@ fn main() -> ! {
 //
 //    Why is it important that ordering of volatile operations are ensured by the compiler?
 //
-//    ** your answer here **
+//    ** If read/write instructions are reordered, the consequences are undefined, since peripherals
+//    depend on the contents of registers that are read from/written to. **
 //
 //    Give an example in the above code, where reordering might make things go horribly wrong
 //    (hint, accessing a peripheral not being powered...)