Merge pull request #2347 from rust-lang/rustc-pull

Rustc pull update

8 files changed, 120 insertions, 55 deletions

diff --git a/compiler/rustc_ty_utils/src/abi.rs b/compiler/rustc_ty_utils/src/abi.rs
index 48d5a4a0fcb..3d4ab33240a 100644
--- a/compiler/rustc_ty_utils/src/abi.rs
+++ b/compiler/rustc_ty_utils/src/abi.rs
@@ -244,7 +244,7 @@ fn fn_sig_for_fn_abi<'tcx>(
 fn conv_from_spec_abi(tcx: TyCtxt<'_>, abi: ExternAbi, c_variadic: bool) -> Conv {
     use rustc_abi::ExternAbi::*;
     match tcx.sess.target.adjust_abi(abi, c_variadic) {
-        RustIntrinsic | Rust | RustCall => Conv::Rust,
+        Rust | RustCall => Conv::Rust,
 
         // This is intentionally not using `Conv::Cold`, as that has to preserve
         // even SIMD registers, which is generally not a good trade-off.
@@ -660,7 +660,7 @@ fn fn_abi_adjust_for_abi<'tcx>(
     let tcx = cx.tcx();
 
     if abi.is_rustic_abi() {
-        fn_abi.adjust_for_rust_abi(cx, abi);
+        fn_abi.adjust_for_rust_abi(cx);
 
         // Look up the deduced parameter attributes for this function, if we have its def ID and
         // we're optimizing in non-incremental mode. We'll tag its parameters with those attributes
diff --git a/compiler/rustc_ty_utils/src/assoc.rs b/compiler/rustc_ty_utils/src/assoc.rs
index b7684e85d41..6cb9fdc6f93 100644
--- a/compiler/rustc_ty_utils/src/assoc.rs
+++ b/compiler/rustc_ty_utils/src/assoc.rs
@@ -6,7 +6,6 @@ use rustc_hir::{self as hir, AmbigArg};
 use rustc_middle::query::Providers;
 use rustc_middle::ty::{self, ImplTraitInTraitData, TyCtxt};
 use rustc_middle::{bug, span_bug};
-use rustc_span::kw;
 
 pub(crate) fn provide(providers: &mut Providers) {
     *providers = Providers {
@@ -129,39 +128,35 @@ fn associated_item(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::AssocItem {
 
 fn associated_item_from_trait_item_ref(trait_item_ref: &hir::TraitItemRef) -> ty::AssocItem {
     let owner_id = trait_item_ref.id.owner_id;
-    let (kind, has_self) = match trait_item_ref.kind {
-        hir::AssocItemKind::Const => (ty::AssocKind::Const, false),
-        hir::AssocItemKind::Fn { has_self } => (ty::AssocKind::Fn, has_self),
-        hir::AssocItemKind::Type => (ty::AssocKind::Type, false),
+    let name = trait_item_ref.ident.name;
+    let kind = match trait_item_ref.kind {
+        hir::AssocItemKind::Const => ty::AssocKind::Const { name },
+        hir::AssocItemKind::Fn { has_self } => ty::AssocKind::Fn { name, has_self },
+        hir::AssocItemKind::Type => ty::AssocKind::Type { data: ty::AssocTypeData::Normal(name) },
     };
 
     ty::AssocItem {
-        name: trait_item_ref.ident.name,
         kind,
         def_id: owner_id.to_def_id(),
         trait_item_def_id: Some(owner_id.to_def_id()),
         container: ty::AssocItemContainer::Trait,
-        fn_has_self_parameter: has_self,
-        opt_rpitit_info: None,
     }
 }
 
 fn associated_item_from_impl_item_ref(impl_item_ref: &hir::ImplItemRef) -> ty::AssocItem {
     let def_id = impl_item_ref.id.owner_id;
-    let (kind, has_self) = match impl_item_ref.kind {
-        hir::AssocItemKind::Const => (ty::AssocKind::Const, false),
-        hir::AssocItemKind::Fn { has_self } => (ty::AssocKind::Fn, has_self),
-        hir::AssocItemKind::Type => (ty::AssocKind::Type, false),
+    let name = impl_item_ref.ident.name;
+    let kind = match impl_item_ref.kind {
+        hir::AssocItemKind::Const => ty::AssocKind::Const { name },
+        hir::AssocItemKind::Fn { has_self } => ty::AssocKind::Fn { name, has_self },
+        hir::AssocItemKind::Type => ty::AssocKind::Type { data: ty::AssocTypeData::Normal(name) },
     };
 
     ty::AssocItem {
-        name: impl_item_ref.ident.name,
         kind,
         def_id: def_id.to_def_id(),
         trait_item_def_id: impl_item_ref.trait_item_def_id,
         container: ty::AssocItemContainer::Impl,
-        fn_has_self_parameter: has_self,
-        opt_rpitit_info: None,
     }
 }
 
@@ -252,7 +247,7 @@ fn associated_type_for_impl_trait_in_trait(
     assert_eq!(tcx.def_kind(trait_def_id), DefKind::Trait);
 
     let span = tcx.def_span(opaque_ty_def_id);
-    // No name because this is a synthetic associated type.
+    // No name because this is an anonymous associated type.
     let trait_assoc_ty = tcx.at(span).create_def(trait_def_id, None, DefKind::AssocTy);
 
     let local_def_id = trait_assoc_ty.def_id();
@@ -264,16 +259,15 @@ fn associated_type_for_impl_trait_in_trait(
     trait_assoc_ty.def_ident_span(Some(span));
 
     trait_assoc_ty.associated_item(ty::AssocItem {
-        name: kw::Empty,
-        kind: ty::AssocKind::Type,
+        kind: ty::AssocKind::Type {
+            data: ty::AssocTypeData::Rpitit(ImplTraitInTraitData::Trait {
+                fn_def_id: fn_def_id.to_def_id(),
+                opaque_def_id: opaque_ty_def_id.to_def_id(),
+            }),
+        },
         def_id,
         trait_item_def_id: None,
         container: ty::AssocItemContainer::Trait,
-        fn_has_self_parameter: false,
-        opt_rpitit_info: Some(ImplTraitInTraitData::Trait {
-            fn_def_id: fn_def_id.to_def_id(),
-            opaque_def_id: opaque_ty_def_id.to_def_id(),
-        }),
     });
 
     // Copy visility of the containing function.
@@ -305,7 +299,7 @@ fn associated_type_for_impl_trait_in_impl(
         hir::FnRetTy::DefaultReturn(_) => tcx.def_span(impl_fn_def_id),
         hir::FnRetTy::Return(ty) => ty.span,
     };
-    // No name because this is a synthetic associated type.
+    // No name because this is an anonymous associated type.
     let impl_assoc_ty = tcx.at(span).create_def(impl_local_def_id, None, DefKind::AssocTy);
 
     let local_def_id = impl_assoc_ty.def_id();
@@ -317,13 +311,14 @@ fn associated_type_for_impl_trait_in_impl(
     impl_assoc_ty.def_ident_span(Some(span));
 
     impl_assoc_ty.associated_item(ty::AssocItem {
-        name: kw::Empty,
-        kind: ty::AssocKind::Type,
+        kind: ty::AssocKind::Type {
+            data: ty::AssocTypeData::Rpitit(ImplTraitInTraitData::Impl {
+                fn_def_id: impl_fn_def_id.to_def_id(),
+            }),
+        },
         def_id,
         trait_item_def_id: Some(trait_assoc_def_id),
         container: ty::AssocItemContainer::Impl,
-        fn_has_self_parameter: false,
-        opt_rpitit_info: Some(ImplTraitInTraitData::Impl { fn_def_id: impl_fn_def_id.to_def_id() }),
     });
 
     // Copy visility of the containing function.
diff --git a/compiler/rustc_ty_utils/src/implied_bounds.rs b/compiler/rustc_ty_utils/src/implied_bounds.rs
index 088d5e76b86..6fa763f18ef 100644
--- a/compiler/rustc_ty_utils/src/implied_bounds.rs
+++ b/compiler/rustc_ty_utils/src/implied_bounds.rs
@@ -4,9 +4,9 @@ use rustc_data_structures::fx::FxHashMap;
 use rustc_hir as hir;
 use rustc_hir::def::DefKind;
 use rustc_hir::def_id::LocalDefId;
-use rustc_middle::bug;
 use rustc_middle::query::Providers;
 use rustc_middle::ty::{self, Ty, TyCtxt, fold_regions};
+use rustc_middle::{bug, span_bug};
 use rustc_span::Span;
 
 pub(crate) fn provide(providers: &mut Providers) {
@@ -21,7 +21,8 @@ pub(crate) fn provide(providers: &mut Providers) {
 }
 
 fn assumed_wf_types<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalDefId) -> &'tcx [(Ty<'tcx>, Span)] {
-    match tcx.def_kind(def_id) {
+    let kind = tcx.def_kind(def_id);
+    match kind {
         DefKind::Fn => {
             let sig = tcx.fn_sig(def_id).instantiate_identity();
             let liberated_sig = tcx.liberate_late_bound_regions(def_id.to_def_id(), sig);
@@ -75,7 +76,7 @@ fn assumed_wf_types<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalDefId) -> &'tcx [(Ty<'
                     {
                         let orig_lt =
                             tcx.map_opaque_lifetime_to_parent_lifetime(param.def_id.expect_local());
-                        if matches!(*orig_lt, ty::ReLateParam(..)) {
+                        if matches!(orig_lt.kind(), ty::ReLateParam(..)) {
                             mapping.insert(
                                 orig_lt,
                                 ty::Region::new_early_param(
@@ -121,32 +122,38 @@ fn assumed_wf_types<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalDefId) -> &'tcx [(Ty<'
             }
         }
         DefKind::AssocConst | DefKind::AssocTy => tcx.assumed_wf_types(tcx.local_parent(def_id)),
-        DefKind::OpaqueTy => bug!("implied bounds are not defined for opaques"),
-        DefKind::Mod
+        DefKind::Static { .. }
+        | DefKind::Const
+        | DefKind::AnonConst
+        | DefKind::InlineConst
         | DefKind::Struct
         | DefKind::Union
         | DefKind::Enum
-        | DefKind::Variant
         | DefKind::Trait
-        | DefKind::TyAlias
-        | DefKind::ForeignTy
         | DefKind::TraitAlias
+        | DefKind::TyAlias => ty::List::empty(),
+        DefKind::OpaqueTy
+        | DefKind::Mod
+        | DefKind::Variant
+        | DefKind::ForeignTy
         | DefKind::TyParam
-        | DefKind::Const
         | DefKind::ConstParam
-        | DefKind::Static { .. }
         | DefKind::Ctor(_, _)
         | DefKind::Macro(_)
         | DefKind::ExternCrate
         | DefKind::Use
         | DefKind::ForeignMod
-        | DefKind::AnonConst
-        | DefKind::InlineConst
         | DefKind::Field
         | DefKind::LifetimeParam
         | DefKind::GlobalAsm
         | DefKind::Closure
-        | DefKind::SyntheticCoroutineBody => ty::List::empty(),
+        | DefKind::SyntheticCoroutineBody => {
+            span_bug!(
+                tcx.def_span(def_id),
+                "`assumed_wf_types` not defined for {} `{def_id:?}`",
+                kind.descr(def_id.to_def_id())
+            );
+        }
     }
 }
 
diff --git a/compiler/rustc_ty_utils/src/layout.rs b/compiler/rustc_ty_utils/src/layout.rs
index 0017186c1b0..1915ba623cb 100644
--- a/compiler/rustc_ty_utils/src/layout.rs
+++ b/compiler/rustc_ty_utils/src/layout.rs
@@ -514,6 +514,9 @@ fn layout_of_uncached<'tcx>(
                 return map_layout(cx.calc.layout_of_union(&def.repr(), &variants));
             }
 
+            // UnsafeCell and UnsafePinned both disable niche optimizations
+            let is_special_no_niche = def.is_unsafe_cell() || def.is_unsafe_pinned();
+
             let get_discriminant_type =
                 |min, max| abi::Integer::repr_discr(tcx, ty, &def.repr(), min, max);
 
@@ -542,7 +545,7 @@ fn layout_of_uncached<'tcx>(
                     &def.repr(),
                     &variants,
                     def.is_enum(),
-                    def.is_unsafe_cell(),
+                    is_special_no_niche,
                     tcx.layout_scalar_valid_range(def.did()),
                     get_discriminant_type,
                     discriminants_iter(),
@@ -568,7 +571,7 @@ fn layout_of_uncached<'tcx>(
                     &def.repr(),
                     &variants,
                     def.is_enum(),
-                    def.is_unsafe_cell(),
+                    is_special_no_niche,
                     tcx.layout_scalar_valid_range(def.did()),
                     get_discriminant_type,
                     discriminants_iter(),
diff --git a/compiler/rustc_ty_utils/src/lib.rs b/compiler/rustc_ty_utils/src/lib.rs
index 143b7d53880..35cc6f39856 100644
--- a/compiler/rustc_ty_utils/src/lib.rs
+++ b/compiler/rustc_ty_utils/src/lib.rs
@@ -6,7 +6,6 @@
 
 // tidy-alphabetical-start
 #![allow(internal_features)]
-#![cfg_attr(doc, recursion_limit = "256")] // FIXME(nnethercote): will be removed by #124141
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
 #![doc(rust_logo)]
 #![feature(assert_matches)]
diff --git a/compiler/rustc_ty_utils/src/opaque_types.rs b/compiler/rustc_ty_utils/src/opaque_types.rs
index 3aad97d86cc..cd730aeeea9 100644
--- a/compiler/rustc_ty_utils/src/opaque_types.rs
+++ b/compiler/rustc_ty_utils/src/opaque_types.rs
@@ -3,10 +3,10 @@ use rustc_hir::def::DefKind;
 use rustc_hir::def_id::LocalDefId;
 use rustc_hir::intravisit;
 use rustc_hir::intravisit::Visitor;
-use rustc_middle::bug;
 use rustc_middle::query::Providers;
 use rustc_middle::ty::util::{CheckRegions, NotUniqueParam};
 use rustc_middle::ty::{self, Ty, TyCtxt, TypeSuperVisitable, TypeVisitable, TypeVisitor};
+use rustc_middle::{bug, span_bug};
 use rustc_span::Span;
 use tracing::{instrument, trace};
 
@@ -320,9 +320,12 @@ fn opaque_types_defined_by<'tcx>(
         | DefKind::AnonConst => {
             collector.collect_taits_declared_in_body();
         }
+        // Closures and coroutines are type checked with their parent
+        DefKind::Closure | DefKind::InlineConst => {
+            collector.opaques.extend(tcx.opaque_types_defined_by(tcx.local_parent(item)));
+        }
+        DefKind::AssocTy | DefKind::TyAlias | DefKind::GlobalAsm => {}
         DefKind::OpaqueTy
-        | DefKind::TyAlias
-        | DefKind::AssocTy
         | DefKind::Mod
         | DefKind::Struct
         | DefKind::Union
@@ -340,12 +343,13 @@ fn opaque_types_defined_by<'tcx>(
         | DefKind::ForeignMod
         | DefKind::Field
         | DefKind::LifetimeParam
-        | DefKind::GlobalAsm
         | DefKind::Impl { .. }
-        | DefKind::SyntheticCoroutineBody => {}
-        // Closures and coroutines are type checked with their parent
-        DefKind::Closure | DefKind::InlineConst => {
-            collector.opaques.extend(tcx.opaque_types_defined_by(tcx.local_parent(item)));
+        | DefKind::SyntheticCoroutineBody => {
+            span_bug!(
+                tcx.def_span(item),
+                "`opaque_types_defined_by` not defined for {} `{item:?}`",
+                kind.descr(item.to_def_id())
+            );
         }
     }
     tcx.mk_local_def_ids(&collector.opaques)
diff --git a/compiler/rustc_ty_utils/src/sig_types.rs b/compiler/rustc_ty_utils/src/sig_types.rs
index 5bb96f90029..dc6009116ac 100644
--- a/compiler/rustc_ty_utils/src/sig_types.rs
+++ b/compiler/rustc_ty_utils/src/sig_types.rs
@@ -116,7 +116,7 @@ pub fn walk_types<'tcx, V: SpannedTypeVisitor<'tcx>>(
                 "{kind:?} has not seen any uses of `walk_types` yet, ping oli-obk if you'd like any help"
             )
         }
-        // These don't have any types.
+        // These don't have any types, but are visited during privacy checking.
         | DefKind::ExternCrate
         | DefKind::ForeignMod
         | DefKind::ForeignTy
diff --git a/compiler/rustc_ty_utils/src/ty.rs b/compiler/rustc_ty_utils/src/ty.rs
index 9dc4f11e456..31d69eef5ec 100644
--- a/compiler/rustc_ty_utils/src/ty.rs
+++ b/compiler/rustc_ty_utils/src/ty.rs
@@ -3,6 +3,7 @@ use rustc_hir as hir;
 use rustc_hir::LangItem;
 use rustc_hir::def::DefKind;
 use rustc_index::bit_set::DenseBitSet;
+use rustc_infer::infer::TyCtxtInferExt;
 use rustc_middle::bug;
 use rustc_middle::query::Providers;
 use rustc_middle::ty::{
@@ -312,6 +313,61 @@ fn unsizing_params_for_adt<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> DenseBitSe
     unsizing_params
 }
 
+fn impl_self_is_guaranteed_unsized<'tcx>(tcx: TyCtxt<'tcx>, impl_def_id: DefId) -> bool {
+    debug_assert_eq!(tcx.def_kind(impl_def_id), DefKind::Impl { of_trait: true });
+
+    let infcx = tcx.infer_ctxt().ignoring_regions().build(ty::TypingMode::non_body_analysis());
+
+    let ocx = traits::ObligationCtxt::new_with_diagnostics(&infcx);
+    let cause = traits::ObligationCause::dummy();
+    let param_env = tcx.param_env(impl_def_id);
+
+    let tail = tcx.struct_tail_raw(
+        tcx.type_of(impl_def_id).instantiate_identity(),
+        |ty| {
+            ocx.structurally_normalize_ty(&cause, param_env, ty).unwrap_or_else(|_| {
+                Ty::new_error_with_message(
+                    tcx,
+                    tcx.def_span(impl_def_id),
+                    "struct tail should be computable",
+                )
+            })
+        },
+        || (),
+    );
+
+    match tail.kind() {
+        ty::Dynamic(_, _, ty::Dyn) | ty::Slice(_) | ty::Str => true,
+        ty::Bool
+        | ty::Char
+        | ty::Int(_)
+        | ty::Uint(_)
+        | ty::Float(_)
+        | ty::Adt(_, _)
+        | ty::Foreign(_)
+        | ty::Array(_, _)
+        | ty::Pat(_, _)
+        | ty::RawPtr(_, _)
+        | ty::Ref(_, _, _)
+        | ty::FnDef(_, _)
+        | ty::FnPtr(_, _)
+        | ty::UnsafeBinder(_)
+        | ty::Closure(_, _)
+        | ty::CoroutineClosure(_, _)
+        | ty::Coroutine(_, _)
+        | ty::CoroutineWitness(_, _)
+        | ty::Never
+        | ty::Tuple(_)
+        | ty::Alias(_, _)
+        | ty::Param(_)
+        | ty::Bound(_, _)
+        | ty::Placeholder(_)
+        | ty::Infer(_)
+        | ty::Error(_)
+        | ty::Dynamic(_, _, ty::DynStar) => false,
+    }
+}
+
 pub(crate) fn provide(providers: &mut Providers) {
     *providers = Providers {
         asyncness,
@@ -320,6 +376,7 @@ pub(crate) fn provide(providers: &mut Providers) {
         param_env_normalized_for_post_analysis,
         defaultness,
         unsizing_params_for_adt,
+        impl_self_is_guaranteed_unsized,
         ..*providers
     };
 }