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`.

2 files changed, 14 insertions, 15 deletions

diff --git a/compiler/rustc_mir_dataflow/src/elaborate_drops.rs b/compiler/rustc_mir_dataflow/src/elaborate_drops.rs
index 9a1f000d39d..494b7d54d8a 100644
--- a/compiler/rustc_mir_dataflow/src/elaborate_drops.rs
+++ b/compiler/rustc_mir_dataflow/src/elaborate_drops.rs
@@ -6,7 +6,6 @@ use rustc_index::Idx;
 use rustc_middle::mir::patch::MirPatch;
 use rustc_middle::mir::*;
 use rustc_middle::span_bug;
-use rustc_middle::traits::Reveal;
 use rustc_middle::ty::util::IntTypeExt;
 use rustc_middle::ty::{self, GenericArgsRef, Ty, TyCtxt};
 use rustc_span::DUMMY_SP;
@@ -111,7 +110,7 @@ pub trait DropElaborator<'a, 'tcx>: fmt::Debug {
     fn patch(&mut self) -> &mut MirPatch<'tcx>;
     fn body(&self) -> &'a Body<'tcx>;
     fn tcx(&self) -> TyCtxt<'tcx>;
-    fn param_env(&self) -> ty::ParamEnv<'tcx>;
+    fn typing_env(&self) -> ty::TypingEnv<'tcx>;
 
     // Drop logic
 
@@ -273,9 +272,9 @@ where
                 let subpath = self.elaborator.field_subpath(variant_path, field);
                 let tcx = self.tcx();
 
-                assert_eq!(self.elaborator.param_env().reveal(), Reveal::All);
+                assert_eq!(self.elaborator.typing_env().typing_mode, ty::TypingMode::PostAnalysis);
                 let field_ty =
-                    tcx.normalize_erasing_regions(self.elaborator.param_env(), f.ty(tcx, args));
+                    tcx.normalize_erasing_regions(self.elaborator.typing_env(), f.ty(tcx, args));
 
                 (tcx.mk_place_field(base_place, field, field_ty), subpath)
             })
@@ -372,7 +371,7 @@ where
 
         let mut fields = fields;
         fields.retain(|&(place, _)| {
-            self.place_ty(place).needs_drop(self.tcx(), self.elaborator.param_env())
+            self.place_ty(place).needs_drop(self.tcx(), self.elaborator.typing_env())
         });
 
         debug!("drop_ladder - fields needing drop: {:?}", fields);
@@ -544,11 +543,11 @@ where
             } else {
                 have_otherwise = true;
 
-                let param_env = self.elaborator.param_env();
+                let typing_env = self.elaborator.typing_env();
                 let have_field_with_drop_glue = variant
                     .fields
                     .iter()
-                    .any(|field| field.ty(tcx, args).needs_drop(tcx, param_env));
+                    .any(|field| field.ty(tcx, args).needs_drop(tcx, typing_env));
                 if have_field_with_drop_glue {
                     have_otherwise_with_drop_glue = true;
                 }
diff --git a/compiler/rustc_mir_dataflow/src/value_analysis.rs b/compiler/rustc_mir_dataflow/src/value_analysis.rs
index af2d514fc76..ed8678de1eb 100644
--- a/compiler/rustc_mir_dataflow/src/value_analysis.rs
+++ b/compiler/rustc_mir_dataflow/src/value_analysis.rs
@@ -462,7 +462,7 @@ impl<'tcx> Map<'tcx> {
         drop(assignments);
 
         // Create values for places whose type have scalar layout.
-        let param_env = tcx.param_env_reveal_all_normalized(body.source.def_id());
+        let typing_env = body.typing_env(tcx);
         for place_info in self.places.iter_mut() {
             // The user requires a bound on the number of created values.
             if let Some(value_limit) = value_limit
@@ -471,13 +471,13 @@ impl<'tcx> Map<'tcx> {
                 break;
             }
 
-            if let Ok(ty) = tcx.try_normalize_erasing_regions(param_env, place_info.ty) {
+            if let Ok(ty) = tcx.try_normalize_erasing_regions(typing_env, place_info.ty) {
                 place_info.ty = ty;
             }
 
             // Allocate a value slot if it doesn't have one, and the user requested one.
             assert!(place_info.value_index.is_none());
-            if let Ok(layout) = tcx.layout_of(param_env.and(place_info.ty))
+            if let Ok(layout) = tcx.layout_of(typing_env.as_query_input(place_info.ty))
                 && layout.backend_repr.is_scalar()
             {
                 place_info.value_index = Some(self.value_count.into());
@@ -874,7 +874,7 @@ impl<V, T> TryFrom<ProjectionElem<V, T>> for TrackElem {
 pub fn iter_fields<'tcx>(
     ty: Ty<'tcx>,
     tcx: TyCtxt<'tcx>,
-    param_env: ty::ParamEnv<'tcx>,
+    typing_env: ty::TypingEnv<'tcx>,
     mut f: impl FnMut(Option<VariantIdx>, FieldIdx, Ty<'tcx>),
 ) {
     match ty.kind() {
@@ -892,20 +892,20 @@ pub fn iter_fields<'tcx>(
                 for (f_index, f_def) in v_def.fields.iter().enumerate() {
                     let field_ty = f_def.ty(tcx, args);
                     let field_ty = tcx
-                        .try_normalize_erasing_regions(param_env, field_ty)
+                        .try_normalize_erasing_regions(typing_env, field_ty)
                         .unwrap_or_else(|_| tcx.erase_regions(field_ty));
                     f(variant, f_index.into(), field_ty);
                 }
             }
         }
         ty::Closure(_, args) => {
-            iter_fields(args.as_closure().tupled_upvars_ty(), tcx, param_env, f);
+            iter_fields(args.as_closure().tupled_upvars_ty(), tcx, typing_env, f);
         }
         ty::Coroutine(_, args) => {
-            iter_fields(args.as_coroutine().tupled_upvars_ty(), tcx, param_env, f);
+            iter_fields(args.as_coroutine().tupled_upvars_ty(), tcx, typing_env, f);
         }
         ty::CoroutineClosure(_, args) => {
-            iter_fields(args.as_coroutine_closure().tupled_upvars_ty(), tcx, param_env, f);
+            iter_fields(args.as_coroutine_closure().tupled_upvars_ty(), tcx, typing_env, f);
         }
         _ => (),
     }