Auto merge of #65989 - Aaron1011:fix/normalize-param-env, r=nikomatsakis

Normalize all opaque types when converting ParamEnv to Reveal::All

When we normalize a type using a ParamEnv with a reveal mode of
RevealMode::All, we will normalize opaque types to their underlying
types (e.g. `type MyOpaque = impl Foo` -> `StructThatImplsFoo`).
However, the ParamEnv may still have predicates referring to the
un-normalized opaque type (e.g. `<T as MyTrait<MyOpaque>>`). This can
cause trait projection to fail, since a type containing normalized
opaque types will not match up with the un-normalized type in the
`ParamEnv`.

To fix this, we now explicitly normalize all opaque types in
caller_bounds of a `ParamEnv` when changing its mode to
`RevealMode::All`. This ensures that all predicatse will refer to the
underlying types of any opaque types involved, allowing them to be
matched up properly during projection. To reflect the fact that
normalization is occuring, `ParamEnv::with_reveal_all` is renamed to
`ParamEnv::with_reveal_all_normalized`

Fixes #65918

5 files changed, 5 insertions, 5 deletions

diff --git a/src/librustc_mir/shim.rs b/src/librustc_mir/shim.rs
index bfa9bb9e0f0..6a7653b6075 100644
--- a/src/librustc_mir/shim.rs
+++ b/src/librustc_mir/shim.rs
@@ -193,7 +193,7 @@ fn build_drop_shim<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId, ty: Option<Ty<'tcx>>)
             );
         }
         let patch = {
-            let param_env = tcx.param_env(def_id).with_reveal_all();
+            let param_env = tcx.param_env_reveal_all_normalized(def_id);
             let mut elaborator =
                 DropShimElaborator { body: &body, patch: MirPatch::new(&body), tcx, param_env };
             let dropee = tcx.mk_place_deref(dropee_ptr);
diff --git a/src/librustc_mir/transform/const_prop.rs b/src/librustc_mir/transform/const_prop.rs
index a1db06e6aa3..8e2fd709d66 100644
--- a/src/librustc_mir/transform/const_prop.rs
+++ b/src/librustc_mir/transform/const_prop.rs
@@ -328,7 +328,7 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> {
     ) -> ConstPropagator<'mir, 'tcx> {
         let def_id = source.def_id();
         let substs = &InternalSubsts::identity_for_item(tcx, def_id);
-        let param_env = tcx.param_env(def_id).with_reveal_all();
+        let param_env = tcx.param_env_reveal_all_normalized(def_id);
 
         let span = tcx.def_span(def_id);
         let can_const_prop = CanConstProp::check(body);
diff --git a/src/librustc_mir/transform/elaborate_drops.rs b/src/librustc_mir/transform/elaborate_drops.rs
index d3bfd872d16..ad49090bfc5 100644
--- a/src/librustc_mir/transform/elaborate_drops.rs
+++ b/src/librustc_mir/transform/elaborate_drops.rs
@@ -25,7 +25,7 @@ impl<'tcx> MirPass<'tcx> for ElaborateDrops {
         debug!("elaborate_drops({:?} @ {:?})", src, body.span);
 
         let def_id = src.def_id();
-        let param_env = tcx.param_env(src.def_id()).with_reveal_all();
+        let param_env = tcx.param_env_reveal_all_normalized(src.def_id());
         let move_data = match MoveData::gather_moves(body, tcx, param_env) {
             Ok(move_data) => move_data,
             Err((move_data, _)) => {
diff --git a/src/librustc_mir/transform/inline.rs b/src/librustc_mir/transform/inline.rs
index c03be2a8fcd..92ea162e419 100644
--- a/src/librustc_mir/transform/inline.rs
+++ b/src/librustc_mir/transform/inline.rs
@@ -72,7 +72,7 @@ impl Inliner<'tcx> {
 
         let mut callsites = VecDeque::new();
 
-        let param_env = self.tcx.param_env(self.source.def_id()).with_reveal_all();
+        let param_env = self.tcx.param_env_reveal_all_normalized(self.source.def_id());
 
         // Only do inlining into fn bodies.
         let id = self.tcx.hir().as_local_hir_id(self.source.def_id().expect_local());
diff --git a/src/librustc_mir/transform/validate.rs b/src/librustc_mir/transform/validate.rs
index e794a6949d2..b8a74f09409 100644
--- a/src/librustc_mir/transform/validate.rs
+++ b/src/librustc_mir/transform/validate.rs
@@ -189,7 +189,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         // Normalize projections and things like that.
         // FIXME: We need to reveal_all, as some optimizations change types in ways
         // that require unfolding opaque types.
-        let param_env = self.param_env.with_reveal_all();
+        let param_env = self.param_env.with_reveal_all_normalized(self.tcx);
         let src = self.tcx.normalize_erasing_regions(param_env, src);
         let dest = self.tcx.normalize_erasing_regions(param_env, dest);