Auto merge of rust-lang#139979 - matthiaskrgr:rollup-7wu5169, r=matthiaskrgr

Rollup of 9 pull requests

Successful merges:

 - rust-lang#139774 (Fix replacing supertrait aliases in `ReplaceProjectionWith`)
 - rust-lang#139850 (Hide unstable print kinds within emit_unknown_print_request_help in stable channel)
 - rust-lang#139870 (add retries to remove and create dir all)
 - rust-lang#139902 (do not emit `OpaqueCast` projections with `-Znext-solver`)
 - rust-lang#139931 (bootstrap: enable zlib for LLVM for Windows GNU)
 - rust-lang#139935 (Upgrade to `rustc-rayon-core` 0.5.1)
 - rust-lang#139943 (rustdoc: Support inlined cross-crate re-exported trait aliases)
 - rust-lang#139961 (Two `rustc_const_eval` cleanups)
 - rust-lang#139962 (opt-dist: add a flag for running tests)

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors

Diff for: Cargo.lock

@@ -3199,14 +3199,12 @@ dependencies = [
 
 [[package]]
 name = "rustc-rayon-core"
-version = "0.5.0"
+version = "0.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "67668daaf00e359c126f6dcb40d652d89b458a008c8afa727a42a2d20fca0b7f"
+checksum = "2f42932dcd3bcbe484b38a3ccf79b7906fac41c02d408b5b1bac26da3416efdb"
 dependencies = [
- "crossbeam-channel",
  "crossbeam-deque",
  "crossbeam-utils",
- "num_cpus",
 ]
 
 [[package]]

Diff for: compiler/rustc_const_eval/src/check_consts/check.rs

@@ -34,7 +34,7 @@ use crate::check_consts::is_fn_or_trait_safe_to_expose_on_stable;
 use crate::errors;
 
 type QualifResults<'mir, 'tcx, Q> =
-    rustc_mir_dataflow::ResultsCursor<'mir, 'tcx, FlowSensitiveAnalysis<'mir, 'mir, 'tcx, Q>>;
+    rustc_mir_dataflow::ResultsCursor<'mir, 'tcx, FlowSensitiveAnalysis<'mir, 'tcx, Q>>;
 
 #[derive(Copy, Clone, PartialEq, Eq, Debug)]
 enum ConstConditionsHold {

Diff for: compiler/rustc_const_eval/src/check_consts/resolver.rs

@@ -22,17 +22,17 @@ use super::{ConstCx, Qualif, qualifs};
 /// qualified immediately after it is borrowed or its address escapes. The borrow must allow for
 /// mutation, which includes shared borrows of places with interior mutability. The type of
 /// borrowed place must contain the qualif.
-struct TransferFunction<'a, 'mir, 'tcx, Q> {
-    ccx: &'a ConstCx<'mir, 'tcx>,
-    state: &'a mut State,
+struct TransferFunction<'mir, 'tcx, Q> {
+    ccx: &'mir ConstCx<'mir, 'tcx>,
+    state: &'mir mut State,
     _qualif: PhantomData<Q>,
 }
 
-impl<'a, 'mir, 'tcx, Q> TransferFunction<'a, 'mir, 'tcx, Q>
+impl<'mir, 'tcx, Q> TransferFunction<'mir, 'tcx, Q>
 where
     Q: Qualif,
 {
-    fn new(ccx: &'a ConstCx<'mir, 'tcx>, state: &'a mut State) -> Self {
+    fn new(ccx: &'mir ConstCx<'mir, 'tcx>, state: &'mir mut State) -> Self {
         TransferFunction { ccx, state, _qualif: PhantomData }
     }
 
@@ -124,7 +124,7 @@ where
     }
 }
 
-impl<'tcx, Q> Visitor<'tcx> for TransferFunction<'_, '_, 'tcx, Q>
+impl<'tcx, Q> Visitor<'tcx> for TransferFunction<'_, 'tcx, Q>
 where
     Q: Qualif,
 {
@@ -228,20 +228,20 @@ where
 }
 
 /// The dataflow analysis used to propagate qualifs on arbitrary CFGs.
-pub(super) struct FlowSensitiveAnalysis<'a, 'mir, 'tcx, Q> {
-    ccx: &'a ConstCx<'mir, 'tcx>,
+pub(super) struct FlowSensitiveAnalysis<'mir, 'tcx, Q> {
+    ccx: &'mir ConstCx<'mir, 'tcx>,
     _qualif: PhantomData<Q>,
 }
 
-impl<'a, 'mir, 'tcx, Q> FlowSensitiveAnalysis<'a, 'mir, 'tcx, Q>
+impl<'mir, 'tcx, Q> FlowSensitiveAnalysis<'mir, 'tcx, Q>
 where
     Q: Qualif,
 {
-    pub(super) fn new(_: Q, ccx: &'a ConstCx<'mir, 'tcx>) -> Self {
+    pub(super) fn new(_: Q, ccx: &'mir ConstCx<'mir, 'tcx>) -> Self {
         FlowSensitiveAnalysis { ccx, _qualif: PhantomData }
     }
 
-    fn transfer_function(&self, state: &'a mut State) -> TransferFunction<'a, 'mir, 'tcx, Q> {
+    fn transfer_function(&self, state: &'mir mut State) -> TransferFunction<'mir, 'tcx, Q> {
         TransferFunction::<Q>::new(self.ccx, state)
     }
 }
@@ -313,7 +313,7 @@ impl JoinSemiLattice for State {
     }
 }
 
-impl<'tcx, Q> Analysis<'tcx> for FlowSensitiveAnalysis<'_, '_, 'tcx, Q>
+impl<'tcx, Q> Analysis<'tcx> for FlowSensitiveAnalysis<'_, 'tcx, Q>
 where
     Q: Qualif,
 {

Diff for: compiler/rustc_const_eval/src/interpret/intern.rs

@@ -30,6 +30,7 @@ use super::{
     AllocId, Allocation, InterpCx, MPlaceTy, Machine, MemoryKind, PlaceTy, err_ub, interp_ok,
 };
 use crate::const_eval;
+use crate::const_eval::DummyMachine;
 use crate::errors::NestedStaticInThreadLocal;
 
 pub trait CompileTimeMachine<'tcx, T> = Machine<
@@ -323,14 +324,17 @@ pub fn intern_const_alloc_for_constprop<'tcx, T, M: CompileTimeMachine<'tcx, T>>
     interp_ok(())
 }
 
-impl<'tcx, M: super::intern::CompileTimeMachine<'tcx, !>> InterpCx<'tcx, M> {
+impl<'tcx> InterpCx<'tcx, DummyMachine> {
     /// A helper function that allocates memory for the layout given and gives you access to mutate
     /// it. Once your own mutation code is done, the backing `Allocation` is removed from the
     /// current `Memory` and interned as read-only into the global memory.
     pub fn intern_with_temp_alloc(
         &mut self,
         layout: TyAndLayout<'tcx>,
-        f: impl FnOnce(&mut InterpCx<'tcx, M>, &PlaceTy<'tcx, M::Provenance>) -> InterpResult<'tcx, ()>,
+        f: impl FnOnce(
+            &mut InterpCx<'tcx, DummyMachine>,
+            &PlaceTy<'tcx, CtfeProvenance>,
+        ) -> InterpResult<'tcx, ()>,
     ) -> InterpResult<'tcx, AllocId> {
         // `allocate` picks a fresh AllocId that we will associate with its data below.
         let dest = self.allocate(layout, MemoryKind::Stack)?;

Diff for: compiler/rustc_hir_typeck/src/expr_use_visitor.rs

@@ -1502,16 +1502,21 @@ impl<'tcx, Cx: TypeInformationCtxt<'tcx>, D: Delegate<'tcx>> ExprUseVisitor<'tcx
         let mut projections = base_place.place.projections;
 
         let node_ty = self.cx.typeck_results().node_type(node);
-        // Opaque types can't have field projections, but we can instead convert
-        // the current place in-place (heh) to the hidden type, and then apply all
-        // follow up projections on that.
-        if node_ty != place_ty
-            && self
-                .cx
-                .try_structurally_resolve_type(self.cx.tcx().hir_span(base_place.hir_id), place_ty)
-                .is_impl_trait()
-        {
-            projections.push(Projection { kind: ProjectionKind::OpaqueCast, ty: node_ty });
+        if !self.cx.tcx().next_trait_solver_globally() {
+            // Opaque types can't have field projections, but we can instead convert
+            // the current place in-place (heh) to the hidden type, and then apply all
+            // follow up projections on that.
+            if node_ty != place_ty
+                && self
+                    .cx
+                    .try_structurally_resolve_type(
+                        self.cx.tcx().hir_span(base_place.hir_id),
+                        place_ty,
+                    )
+                    .is_impl_trait()
+            {
+                projections.push(Projection { kind: ProjectionKind::OpaqueCast, ty: node_ty });
+            }
         }
         projections.push(Projection { kind, ty });
         PlaceWithHirId::new(node, base_place.place.base_ty, base_place.place.base, projections)

Diff for: compiler/rustc_middle/src/hir/place.rs

@@ -40,6 +40,8 @@ pub enum ProjectionKind {
 
     /// A conversion from an opaque type to its hidden type so we can
     /// do further projections on it.
+    ///
+    /// This is unused if `-Znext-solver` is enabled.
     OpaqueCast,
 }
 

Diff for: compiler/rustc_middle/src/mir/syntax.rs

@@ -1242,6 +1242,8 @@ pub enum ProjectionElem<V, T> {
 
     /// Like an explicit cast from an opaque type to a concrete type, but without
     /// requiring an intermediate variable.
+    ///
+    /// This is unused with `-Znext-solver`.
     OpaqueCast(T),
 
     /// A transmute from an unsafe binder to the type that it wraps. This is a projection

Diff for: compiler/rustc_mir_build/src/builder/matches/match_pair.rs

@@ -101,18 +101,21 @@ impl<'tcx> MatchPairTree<'tcx> {
             place_builder = resolved;
         }
 
-        // Only add the OpaqueCast projection if the given place is an opaque type and the
-        // expected type from the pattern is not.
-        let may_need_cast = match place_builder.base() {
-            PlaceBase::Local(local) => {
-                let ty =
-                    Place::ty_from(local, place_builder.projection(), &cx.local_decls, cx.tcx).ty;
-                ty != pattern.ty && ty.has_opaque_types()
+        if !cx.tcx.next_trait_solver_globally() {
+            // Only add the OpaqueCast projection if the given place is an opaque type and the
+            // expected type from the pattern is not.
+            let may_need_cast = match place_builder.base() {
+                PlaceBase::Local(local) => {
+                    let ty =
+                        Place::ty_from(local, place_builder.projection(), &cx.local_decls, cx.tcx)
+                            .ty;
+                    ty != pattern.ty && ty.has_opaque_types()
+                }
+                _ => true,
+            };
+            if may_need_cast {
+                place_builder = place_builder.project(ProjectionElem::OpaqueCast(pattern.ty));
             }
-            _ => true,
-        };
-        if may_need_cast {
-            place_builder = place_builder.project(ProjectionElem::OpaqueCast(pattern.ty));
         }
 
         let place = place_builder.try_to_place(cx);

Diff for: compiler/rustc_mir_transform/src/post_analysis_normalize.rs

@@ -39,20 +39,22 @@ impl<'tcx> MutVisitor<'tcx> for PostAnalysisNormalizeVisitor<'tcx> {
         _context: PlaceContext,
         _location: Location,
     ) {
-        // Performance optimization: don't reintern if there is no `OpaqueCast` to remove.
-        if place.projection.iter().all(|elem| !matches!(elem, ProjectionElem::OpaqueCast(_))) {
-            return;
+        if !self.tcx.next_trait_solver_globally() {
+            // `OpaqueCast` projections are only needed if there are opaque types on which projections
+            // are performed. After the `PostAnalysisNormalize` pass, all opaque types are replaced with their
+            // hidden types, so we don't need these projections anymore.
+            //
+            // Performance optimization: don't reintern if there is no `OpaqueCast` to remove.
+            if place.projection.iter().any(|elem| matches!(elem, ProjectionElem::OpaqueCast(_))) {
+                place.projection = self.tcx.mk_place_elems(
+                    &place
+                        .projection
+                        .into_iter()
+                        .filter(|elem| !matches!(elem, ProjectionElem::OpaqueCast(_)))
+                        .collect::<Vec<_>>(),
+                );
+            };
         }
-        // `OpaqueCast` projections are only needed if there are opaque types on which projections
-        // are performed. After the `PostAnalysisNormalize` pass, all opaque types are replaced with their
-        // hidden types, so we don't need these projections anymore.
-        place.projection = self.tcx.mk_place_elems(
-            &place
-                .projection
-                .into_iter()
-                .filter(|elem| !matches!(elem, ProjectionElem::OpaqueCast(_)))
-                .collect::<Vec<_>>(),
-        );
         self.super_place(place, _context, _location);
     }
 

Diff for: compiler/rustc_next_trait_solver/src/solve/assembly/mod.rs

@@ -92,16 +92,20 @@ where
             let ty::Dynamic(bounds, _, _) = goal.predicate.self_ty().kind() else {
                 panic!("expected object type in `probe_and_consider_object_bound_candidate`");
             };
-            ecx.add_goals(
-                GoalSource::ImplWhereBound,
-                structural_traits::predicates_for_object_candidate(
-                    ecx,
-                    goal.param_env,
-                    goal.predicate.trait_ref(cx),
-                    bounds,
-                ),
-            );
-            ecx.evaluate_added_goals_and_make_canonical_response(Certainty::Yes)
+            match structural_traits::predicates_for_object_candidate(
+                ecx,
+                goal.param_env,
+                goal.predicate.trait_ref(cx),
+                bounds,
+            ) {
+                Ok(requirements) => {
+                    ecx.add_goals(GoalSource::ImplWhereBound, requirements);
+                    ecx.evaluate_added_goals_and_make_canonical_response(Certainty::Yes)
+                }
+                Err(_) => {
+                    ecx.evaluate_added_goals_and_make_canonical_response(Certainty::AMBIGUOUS)
+                }
+            }
         })
     }