From c9159262d161cd64d828f7821dca5e07926e34f2 Mon Sep 17 00:00:00 2001
From: Santiago Pastorino <spastorino@gmail.com>
Date: Mon, 20 Nov 2017 11:09:45 -0300
Subject: [PATCH] Check NullaryOp Rvalue

---
 src/librustc_mir/transform/type_check.rs | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/src/librustc_mir/transform/type_check.rs b/src/librustc_mir/transform/type_check.rs
index 3599a3174f7..6c6ae3d02da 100644
--- a/src/librustc_mir/transform/type_check.rs
+++ b/src/librustc_mir/transform/type_check.rs
@@ -1137,6 +1137,15 @@ fn check_rvalue(&mut self, mir: &Mir<'tcx>, rvalue: &Rvalue<'tcx>, location: Loc
                 }
             }
 
+            Rvalue::NullaryOp(_, ty) => {
+                let trait_ref = ty::TraitRef {
+                    def_id: tcx.lang_items().sized_trait().unwrap(),
+                    substs: tcx.mk_substs_trait(ty, &[]),
+                };
+
+                self.prove_trait_ref(trait_ref, location);
+            }
+
             // FIXME: These other cases have to be implemented in future PRs
             Rvalue::Use(..) |
             Rvalue::Ref(..) |
@@ -1145,8 +1154,7 @@ fn check_rvalue(&mut self, mir: &Mir<'tcx>, rvalue: &Rvalue<'tcx>, location: Loc
             Rvalue::BinaryOp(..) |
             Rvalue::CheckedBinaryOp(..) |
             Rvalue::UnaryOp(..) |
-            Rvalue::Discriminant(..) |
-            Rvalue::NullaryOp(..) => {}
+            Rvalue::Discriminant(..) => {}
         }
     }