6 files changed, 20 insertions, 9 deletions
diff --git a/compiler/rustc_typeck/src/variance/constraints.rs b/compiler/rustc_hir_analysis/src/variance/constraints.rs
index d79450e1a..eaf0310d5 100644
--- a/compiler/rustc_typeck/src/variance/constraints.rs
+++ b/compiler/rustc_hir_analysis/src/variance/constraints.rs
@@ -257,7 +257,7 @@ impl<'a, 'tcx> ConstraintContext<'a, 'tcx> {
                 self.add_constraints_from_invariant_substs(current, substs, variance);
             }
 
-            ty::Dynamic(data, r) => {
+            ty::Dynamic(data, r, _) => {
                 // The type `Foo<T+'a>` is contravariant w/r/t `'a`:
                 let contra = self.contravariant(variance);
                 self.add_constraints_from_region(current, r, contra);
@@ -271,11 +271,11 @@ impl<'a, 'tcx> ConstraintContext<'a, 'tcx> {
                 }
 
                 for projection in data.projection_bounds() {
-                    match projection.skip_binder().term {
-                        ty::Term::Ty(ty) => {
+                    match projection.skip_binder().term.unpack() {
+                        ty::TermKind::Ty(ty) => {
                             self.add_constraints_from_ty(current, ty, self.invariant);
                         }
-                        ty::Term::Const(c) => {
+                        ty::TermKind::Const(c) => {
                             self.add_constraints_from_const(current, c, self.invariant)
                         }
                     }
@@ -411,11 +411,7 @@ impl<'a, 'tcx> ConstraintContext<'a, 'tcx> {
                 // way early-bound regions do, so we skip them here.
             }
 
-            ty::ReFree(..)
-            | ty::ReVar(..)
-            | ty::RePlaceholder(..)
-            | ty::ReEmpty(_)
-            | ty::ReErased => {
+            ty::ReFree(..) | ty::ReVar(..) | ty::RePlaceholder(..) | ty::ReErased => {
                 // We don't expect to see anything but 'static or bound
                 // regions when visiting member types or method types.
                 bug!(
diff --git a/compiler/rustc_typeck/src/variance/mod.rs b/compiler/rustc_hir_analysis/src/variance/mod.rs
index 82103c5a0..82103c5a0 100644
--- a/compiler/rustc_typeck/src/variance/mod.rs
+++ b/compiler/rustc_hir_analysis/src/variance/mod.rs
diff --git a/compiler/rustc_typeck/src/variance/solve.rs b/compiler/rustc_hir_analysis/src/variance/solve.rs
index 97aca621a..97aca621a 100644
--- a/compiler/rustc_typeck/src/variance/solve.rs
+++ b/compiler/rustc_hir_analysis/src/variance/solve.rs
diff --git a/compiler/rustc_typeck/src/variance/terms.rs b/compiler/rustc_hir_analysis/src/variance/terms.rs
index 1f763011e..1f763011e 100644
--- a/compiler/rustc_typeck/src/variance/terms.rs
+++ b/compiler/rustc_hir_analysis/src/variance/terms.rs
diff --git a/compiler/rustc_hir_analysis/src/variance/test.rs b/compiler/rustc_hir_analysis/src/variance/test.rs
new file mode 100644
index 000000000..83ed3e44b
--- /dev/null
+++ b/compiler/rustc_hir_analysis/src/variance/test.rs
@@ -0,0 +1,15 @@
+use rustc_errors::struct_span_err;
+use rustc_middle::ty::TyCtxt;
+use rustc_span::symbol::sym;
+
+pub fn test_variance(tcx: TyCtxt<'_>) {
+    // For unit testing: check for a special "rustc_variance"
+    // attribute and report an error with various results if found.
+    for id in tcx.hir().items() {
+        if tcx.has_attr(id.owner_id.to_def_id(), sym::rustc_variance) {
+            let variances_of = tcx.variances_of(id.owner_id);
+            struct_span_err!(tcx.sess, tcx.def_span(id.owner_id), E0208, "{:?}", variances_of)
+                .emit();
+        }
+    }
+}
diff --git a/compiler/rustc_typeck/src/variance/xform.rs b/compiler/rustc_hir_analysis/src/variance/xform.rs
index 027f0859f..027f0859f 100644
--- a/compiler/rustc_typeck/src/variance/xform.rs
+++ b/compiler/rustc_hir_analysis/src/variance/xform.rs