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`.

6 files changed, 31 insertions, 33 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),
             )
         }));
diff --git a/compiler/rustc_const_eval/src/check_consts/mod.rs b/compiler/rustc_const_eval/src/check_consts/mod.rs
index ebdd55a4f70..80d3c6448aa 100644
--- a/compiler/rustc_const_eval/src/check_consts/mod.rs
+++ b/compiler/rustc_const_eval/src/check_consts/mod.rs
@@ -24,17 +24,15 @@ mod resolver;
 pub struct ConstCx<'mir, 'tcx> {
     pub body: &'mir mir::Body<'tcx>,
     pub tcx: TyCtxt<'tcx>,
-    pub param_env: ty::ParamEnv<'tcx>,
+    pub typing_env: ty::TypingEnv<'tcx>,
     pub const_kind: Option<hir::ConstContext>,
 }
 
 impl<'mir, 'tcx> ConstCx<'mir, 'tcx> {
     pub fn new(tcx: TyCtxt<'tcx>, body: &'mir mir::Body<'tcx>) -> Self {
-        let def_id = body.source.def_id().expect_local();
-        let param_env = tcx.param_env(def_id);
-
+        let typing_env = body.typing_env(tcx);
         let const_kind = tcx.hir().body_const_context(body.source.def_id().expect_local());
-        ConstCx { body, tcx, param_env, const_kind }
+        ConstCx { body, tcx, typing_env, const_kind }
     }
 
     pub(crate) fn dcx(&self) -> DiagCtxtHandle<'tcx> {
diff --git a/compiler/rustc_const_eval/src/check_consts/ops.rs b/compiler/rustc_const_eval/src/check_consts/ops.rs
index ca95e42dd2b..8ba6b89aad4 100644
--- a/compiler/rustc_const_eval/src/check_consts/ops.rs
+++ b/compiler/rustc_const_eval/src/check_consts/ops.rs
@@ -120,7 +120,7 @@ impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> {
     #[allow(rustc::untranslatable_diagnostic)]
     fn build_error(&self, ccx: &ConstCx<'_, 'tcx>, _: Span) -> Diag<'tcx> {
         let FnCallNonConst { callee, args, span, call_source } = *self;
-        let ConstCx { tcx, param_env, .. } = *ccx;
+        let ConstCx { tcx, typing_env, .. } = *ccx;
         let caller = ccx.def_id();
 
         let diag_trait = |err, self_ty: Ty<'_>, trait_id| {
@@ -146,13 +146,11 @@ impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> {
                     }
                 }
                 ty::Adt(..) => {
+                    let (infcx, param_env) = tcx.infer_ctxt().build_with_typing_env(typing_env);
                     let obligation =
                         Obligation::new(tcx, ObligationCause::dummy(), param_env, trait_ref);
-
-                    let infcx = tcx.infer_ctxt().build(ccx.body.typing_mode(tcx));
                     let mut selcx = SelectionContext::new(&infcx);
                     let implsrc = selcx.select(&obligation);
-
                     if let Ok(Some(ImplSource::UserDefined(data))) = implsrc {
                         // FIXME(const_trait_impl) revisit this
                         if !tcx.is_const_trait_impl(data.impl_def_id) {
@@ -166,7 +164,7 @@ impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> {
         };
 
         let call_kind =
-            call_kind(tcx, ccx.param_env, callee, args, span, call_source.from_hir_call(), None);
+            call_kind(tcx, ccx.typing_env, callee, args, span, call_source.from_hir_call(), None);
 
         debug!(?call_kind);
 
diff --git a/compiler/rustc_const_eval/src/check_consts/post_drop_elaboration.rs b/compiler/rustc_const_eval/src/check_consts/post_drop_elaboration.rs
index 0173a528c22..f6eb130fbd3 100644
--- a/compiler/rustc_const_eval/src/check_consts/post_drop_elaboration.rs
+++ b/compiler/rustc_const_eval/src/check_consts/post_drop_elaboration.rs
@@ -32,17 +32,15 @@ pub fn checking_enabled(ccx: &ConstCx<'_, '_>) -> bool {
 /// This is separate from the rest of the const checking logic because it must run after drop
 /// elaboration.
 pub fn check_live_drops<'tcx>(tcx: TyCtxt<'tcx>, body: &mir::Body<'tcx>) {
-    let def_id = body.source.def_id().expect_local();
-    let const_kind = tcx.hir().body_const_context(def_id);
-    if const_kind.is_none() {
+    let ccx = ConstCx::new(tcx, body);
+    if ccx.const_kind.is_none() {
         return;
     }
 
-    if tcx.has_attr(def_id, sym::rustc_do_not_const_check) {
+    if tcx.has_attr(body.source.def_id(), sym::rustc_do_not_const_check) {
         return;
     }
 
-    let ccx = ConstCx { body, tcx, const_kind, param_env: tcx.param_env(def_id) };
     if !checking_enabled(&ccx) {
         return;
     }
diff --git a/compiler/rustc_const_eval/src/check_consts/qualifs.rs b/compiler/rustc_const_eval/src/check_consts/qualifs.rs
index 29a08579175..bc416acc58d 100644
--- a/compiler/rustc_const_eval/src/check_consts/qualifs.rs
+++ b/compiler/rustc_const_eval/src/check_consts/qualifs.rs
@@ -106,20 +106,24 @@ impl Qualif for HasMutInterior {
         // Instead we invoke an obligation context manually, and provide the opaque type inference settings
         // that allow the trait solver to just error out instead of cycling.
         let freeze_def_id = cx.tcx.require_lang_item(LangItem::Freeze, Some(cx.body.span));
-
+        // FIXME(#132279): Once we've got a typing mode which reveals opaque types using the HIR
+        // typeck results without causing query cycles, we should use this here instead of defining
+        // opaque types.
+        let typing_env = ty::TypingEnv {
+            typing_mode: ty::TypingMode::analysis_in_body(
+                cx.tcx,
+                cx.body.source.def_id().expect_local(),
+            ),
+            param_env: cx.typing_env.param_env,
+        };
+        let (infcx, param_env) = cx.tcx.infer_ctxt().build_with_typing_env(typing_env);
+        let ocx = ObligationCtxt::new(&infcx);
         let obligation = Obligation::new(
             cx.tcx,
             ObligationCause::dummy_with_span(cx.body.span),
-            cx.param_env,
+            param_env,
             ty::TraitRef::new(cx.tcx, freeze_def_id, [ty::GenericArg::from(ty)]),
         );
-
-        // FIXME(#132279): This should eventually use the already defined hidden types.
-        let infcx = cx.tcx.infer_ctxt().build(ty::TypingMode::analysis_in_body(
-            cx.tcx,
-            cx.body.source.def_id().expect_local(),
-        ));
-        let ocx = ObligationCtxt::new(&infcx);
         ocx.register_obligation(obligation);
         let errors = ocx.select_all_or_error();
         !errors.is_empty()
@@ -156,7 +160,7 @@ impl Qualif for NeedsDrop {
     }
 
     fn in_any_value_of_ty<'tcx>(cx: &ConstCx<'_, 'tcx>, ty: Ty<'tcx>) -> bool {
-        ty.needs_drop(cx.tcx, cx.param_env)
+        ty.needs_drop(cx.tcx, cx.typing_env)
     }
 
     fn in_adt_inherently<'tcx>(
diff --git a/compiler/rustc_const_eval/src/check_consts/resolver.rs b/compiler/rustc_const_eval/src/check_consts/resolver.rs
index 74eb6b37fbb..03624a2ce50 100644
--- a/compiler/rustc_const_eval/src/check_consts/resolver.rs
+++ b/compiler/rustc_const_eval/src/check_consts/resolver.rs
@@ -120,7 +120,10 @@ where
     ///
     /// [rust-lang/unsafe-code-guidelines#134]: https://github.com/rust-lang/unsafe-code-guidelines/issues/134
     fn shared_borrow_allows_mutation(&self, place: mir::Place<'tcx>) -> bool {
-        !place.ty(self.ccx.body, self.ccx.tcx).ty.is_freeze(self.ccx.tcx, self.ccx.param_env)
+        !place
+            .ty(self.ccx.body, self.ccx.tcx)
+            .ty
+            .is_freeze(self.ccx.tcx, self.ccx.typing_env.param_env)
     }
 }