From 3a72238aa6c78d071f4b10d60c76550ccea6493f Mon Sep 17 00:00:00 2001
From: lcnr <rust@lcnr.de>
Date: Fri, 10 Feb 2023 14:58:49 +0100
Subject: [PATCH] revert #107074
---
compiler/rustc_const_eval/src/transform/validate.rs | 11 ++++++++++-
tests/ui/impl-trait/nested-return-type2.rs | 3 +++
tests/ui/impl-trait/nested-return-type2.stderr | 2 +-
3 files changed, 14 insertions(+), 2 deletions(-)
diff --git a/compiler/rustc_const_eval/src/transform/validate.rs b/compiler/rustc_const_eval/src/transform/validate.rs
index 76b316cdf0c3f..56c60d59d2858 100644
--- a/compiler/rustc_const_eval/src/transform/validate.rs
+++ b/compiler/rustc_const_eval/src/transform/validate.rs
@@ -13,7 +13,7 @@ use rustc_middle::mir::{
RetagKind, RuntimePhase, Rvalue, SourceScope, Statement, StatementKind, Terminator,
TerminatorKind, UnOp, START_BLOCK,
};
-use rustc_middle::ty::{self, InstanceDef, ParamEnv, Ty, TyCtxt};
+use rustc_middle::ty::{self, InstanceDef, ParamEnv, Ty, TyCtxt, TypeVisitable};
use rustc_mir_dataflow::impls::MaybeStorageLive;
use rustc_mir_dataflow::storage::always_storage_live_locals;
use rustc_mir_dataflow::{Analysis, ResultsCursor};
@@ -231,6 +231,15 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
return true;
}
+ // We sometimes have to use `defining_opaque_types` for subtyping
+ // to succeed here and figuring out how exactly that should work
+ // is annoying. It is harmless enough to just not validate anything
+ // in that case. We still check this after analysis as all opque
+ // types have been revealed at this point.
+ if (src, dest).has_opaque_types() {
+ return true;
+ }
+
crate::util::is_subtype(self.tcx, self.param_env, src, dest)
}
}
diff --git a/tests/ui/impl-trait/nested-return-type2.rs b/tests/ui/impl-trait/nested-return-type2.rs
index cc1f1f4ec44c8..fe883ce6fc8ed 100644
--- a/tests/ui/impl-trait/nested-return-type2.rs
+++ b/tests/ui/impl-trait/nested-return-type2.rs
@@ -1,4 +1,7 @@
// check-pass
+// compile-flags: -Zvalidate-mir
+
+// Using -Zvalidate-mir as a regression test for #107346.
trait Duh {}
diff --git a/tests/ui/impl-trait/nested-return-type2.stderr b/tests/ui/impl-trait/nested-return-type2.stderr
index 3aed05ca13298..09ad3bd05c1b3 100644
--- a/tests/ui/impl-trait/nested-return-type2.stderr
+++ b/tests/ui/impl-trait/nested-return-type2.stderr
@@ -1,5 +1,5 @@
warning: opaque type `impl Trait<Assoc = impl Send>` does not satisfy its associated type bounds
- --> $DIR/nested-return-type2.rs:25:24
+ --> $DIR/nested-return-type2.rs:28:24
|
LL | type Assoc: Duh;
| --- this associated type bound is unsatisfied for `impl Send`