use `TypingEnv` when no `infcx` is available

the behavior of the type system not only depends on the current
assumptions, but also the currentnphase of the compiler. This is
mostly necessary as we need to decide whether and how to reveal
opaque types. We track this via the `TypingMode`.

1 files changed, 4 insertions, 7 deletions

diff --git a/compiler/rustc_const_eval/src/check_consts/check.rs b/compiler/rustc_const_eval/src/check_consts/check.rs
index ffe32acb316..50e8a168eeb 100644
--- a/compiler/rustc_const_eval/src/check_consts/check.rs
+++ b/compiler/rustc_const_eval/src/check_consts/check.rs
@@ -388,7 +388,7 @@ impl<'mir, 'tcx> Checker<'mir, 'tcx> {
             return false;
         }
 
-        let infcx = tcx.infer_ctxt().build(self.body.typing_mode(tcx));
+        let (infcx, param_env) = tcx.infer_ctxt().build_with_typing_env(self.body.typing_env(tcx));
         let ocx = ObligationCtxt::new_with_diagnostics(&infcx);
 
         let body_id = self.body.source.def_id().expect_local();
@@ -398,11 +398,8 @@ impl<'mir, 'tcx> Checker<'mir, 'tcx> {
                 ty::BoundConstness::Const
             }
         };
-        let const_conditions = ocx.normalize(
-            &ObligationCause::misc(call_span, body_id),
-            self.param_env,
-            const_conditions,
-        );
+        let const_conditions =
+            ocx.normalize(&ObligationCause::misc(call_span, body_id), param_env, const_conditions);
         ocx.register_obligations(const_conditions.into_iter().map(|(trait_ref, span)| {
             Obligation::new(
                 tcx,
@@ -411,7 +408,7 @@ impl<'mir, 'tcx> Checker<'mir, 'tcx> {
                     body_id,
                     ObligationCauseCode::WhereClause(callee, span),
                 ),
-                self.param_env,
+                param_env,
                 trait_ref.to_host_effect_clause(tcx, host_polarity),
             )
         }));