polymorphize: polymorphize shims

This commit removes the restriction of `InstanceDef::Item` on
polymorphization, so that shims can now be polymorphized.

Signed-off-by: David Wood <david.wood@huawei.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs b/compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs
index bd1d99640f8..79f1beb0799 100644
--- a/compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs
+++ b/compiler/rustc_metadata/src/rmeta/decoder/cstore_impl.rs
@@ -84,6 +84,12 @@ impl IntoArgs for (CrateNum, DefId) {
     }
 }
 
+impl IntoArgs for ty::InstanceDef<'tcx> {
+    fn into_args(self) -> (DefId, DefId) {
+        (self.def_id(), self.def_id())
+    }
+}
+
 provide! { <'tcx> tcx, def_id, other, cdata,
     type_of => { cdata.get_type(def_id.index, tcx) }
     generics_of => { cdata.get_generics(def_id.index, tcx.sess) }