diff --git a/src/librustc_mir/shim.rs b/src/librustc_mir/shim.rs
index 039651b7e937..1e0858d68645 100644
--- a/src/librustc_mir/shim.rs
+++ b/src/librustc_mir/shim.rs
@@ -335,6 +335,7 @@ impl<'a, 'tcx> CloneShimBuilder<'a, 'tcx> {
             ),
             IndexVec::new(),
             self.sig.output(),
+            None,
             self.local_decls,
             self.sig.inputs().len(),
             vec![],