diff --git a/src/librustc/middle/ty.rs b/src/librustc/middle/ty.rs
index 3497a8d690479..007733b14d53f 100644
--- a/src/librustc/middle/ty.rs
+++ b/src/librustc/middle/ty.rs
@@ -3283,6 +3283,7 @@ impl FlagComputation {
             }
 
             &TyClosure(_, substs) => {
+                self.add_flags(TypeFlags::HAS_TY_CLOSURE);
                 self.add_flags(TypeFlags::HAS_LOCAL_NAMES);
                 self.add_substs(substs);
             }