minor changes

fix/src/lib.rs

@@ -509,6 +509,9 @@ struct OwnedIr {
 }
 
 impl OwnedIr {
+    /// # Safety
+    ///
+    /// `ir` must be allocated from `bump`.
     unsafe fn new(ir: RawIrRef<'_>, bump: Bump) -> Self {
         Self {
             _bump: bump,