Stop OpaqueTypeDecl from being Copy

Author: oli-obk

compiler/rustc_trait_selection/src/opaque_types.rs

@@ -21,7 +21,7 @@ pub type OpaqueTypeMap<'tcx> = DefIdMap<OpaqueTypeDecl<'tcx>>;
 /// Information about the opaque types whose values we
 /// are inferring in this function (these are the `impl Trait` that
 /// appear in the return type).
-#[derive(Copy, Clone, Debug)]
+#[derive(Clone, Debug)]
 pub struct OpaqueTypeDecl<'tcx> {
     /// The opaque type (`ty::Opaque`) for this declaration.
     pub opaque_type: Ty<'tcx>,

compiler/rustc_typeck/src/check/fn_ctxt/_impl.rs

@@ -399,8 +399,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     }
                 }
             }
-            let _ = opaque_types.insert(ty, decl);
             let _ = opaque_types_vars.insert(decl.concrete_ty, decl.opaque_type);
+            let _ = opaque_types.insert(ty, decl);
         }
 
         value