Rollup of 7 pull requests

compiler/rustc_ast/src/ast.rs

@@ -23,7 +23,7 @@ use std::{cmp, fmt, mem};
 
 pub use GenericArgs::*;
 pub use UnsafeSource::*;
-pub use rustc_ast_ir::{Movability, Mutability};
+pub use rustc_ast_ir::{Movability, Mutability, Pinnedness};
 use rustc_data_structures::packed::Pu128;
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_data_structures::stack::ensure_sufficient_stack;
@@ -2161,6 +2161,10 @@ pub enum TyKind {
     Ptr(MutTy),
     /// A reference (`&'a T` or `&'a mut T`).
     Ref(Option<Lifetime>, MutTy),
+    /// A pinned reference (`&'a pin const T` or `&'a pin mut T`).
+    ///
+    /// Desugars into `Pin<&'a T>` or `Pin<&'a mut T>`.
+    PinnedRef(Option<Lifetime>, MutTy),
     /// A bare function (e.g., `fn(usize) -> bool`).
     BareFn(P<BareFnTy>),
     /// The never type (`!`).
@@ -2501,7 +2505,10 @@ impl Param {
             if ident.name == kw::SelfLower {
                 return match self.ty.kind {
                     TyKind::ImplicitSelf => Some(respan(self.pat.span, SelfKind::Value(mutbl))),
-                    TyKind::Ref(lt, MutTy { ref ty, mutbl }) if ty.kind.is_implicit_self() => {
+                    TyKind::Ref(lt, MutTy { ref ty, mutbl })
+                    | TyKind::PinnedRef(lt, MutTy { ref ty, mutbl })
+                        if ty.kind.is_implicit_self() =>
+                    {
                         Some(respan(self.pat.span, SelfKind::Region(lt, mutbl)))
                     }
                     _ => Some(respan(

compiler/rustc_ast/src/mut_visit.rs

@@ -485,7 +485,7 @@ pub fn walk_ty<T: MutVisitor>(vis: &mut T, ty: &mut P<Ty>) {
         }
         TyKind::Slice(ty) => vis.visit_ty(ty),
         TyKind::Ptr(mt) => vis.visit_mt(mt),
-        TyKind::Ref(lt, mt) => {
+        TyKind::Ref(lt, mt) | TyKind::PinnedRef(lt, mt) => {
             visit_opt(lt, |lt| vis.visit_lifetime(lt));
             vis.visit_mt(mt);
         }

compiler/rustc_ast/src/util/classify.rs

@@ -247,7 +247,9 @@ fn type_trailing_braced_mac_call(mut ty: &ast::Ty) -> Option<&ast::MacCall> {
                 break (mac.args.delim == Delimiter::Brace).then_some(mac);
             }
 
-            ast::TyKind::Ptr(mut_ty) | ast::TyKind::Ref(_, mut_ty) => {
+            ast::TyKind::Ptr(mut_ty)
+            | ast::TyKind::Ref(_, mut_ty)
+            | ast::TyKind::PinnedRef(_, mut_ty) => {
                 ty = &mut_ty.ty;
             }
 

compiler/rustc_ast/src/visit.rs

@@ -499,7 +499,8 @@ pub fn walk_ty<'a, V: Visitor<'a>>(visitor: &mut V, typ: &'a Ty) -> V::Result {
     match kind {
         TyKind::Slice(ty) | TyKind::Paren(ty) => try_visit!(visitor.visit_ty(ty)),
         TyKind::Ptr(MutTy { ty, mutbl: _ }) => try_visit!(visitor.visit_ty(ty)),
-        TyKind::Ref(opt_lifetime, MutTy { ty, mutbl: _ }) => {
+        TyKind::Ref(opt_lifetime, MutTy { ty, mutbl: _ })
+        | TyKind::PinnedRef(opt_lifetime, MutTy { ty, mutbl: _ }) => {
             visit_opt!(visitor, visit_lifetime, opt_lifetime, LifetimeCtxt::Ref);
             try_visit!(visitor.visit_ty(ty));
         }

compiler/rustc_ast_ir/src/lib.rs

@@ -79,3 +79,10 @@ impl Mutability {
         matches!(self, Self::Not)
     }
 }
+
+#[derive(Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Debug, Copy)]
+#[cfg_attr(feature = "nightly", derive(Encodable, Decodable, HashStable_NoContext))]
+pub enum Pinnedness {
+    Not,
+    Pinned,
+}

compiler/rustc_ast_lowering/src/expr.rs

@@ -640,7 +640,8 @@ impl<'hir> LoweringContext<'_, 'hir> {
                     self.lower_span(span),
                     Some(self.allow_gen_future.clone()),
                 );
-                let resume_ty = self.make_lang_item_qpath(hir::LangItem::ResumeTy, unstable_span);
+                let resume_ty =
+                    self.make_lang_item_qpath(hir::LangItem::ResumeTy, unstable_span, None);
                 let input_ty = hir::Ty {
                     hir_id: self.next_id(),
                     kind: hir::TyKind::Path(resume_ty),
@@ -2065,7 +2066,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
         lang_item: hir::LangItem,
         name: Symbol,
     ) -> hir::Expr<'hir> {
-        let qpath = self.make_lang_item_qpath(lang_item, self.lower_span(span));
+        let qpath = self.make_lang_item_qpath(lang_item, self.lower_span(span), None);
         let path = hir::ExprKind::Path(hir::QPath::TypeRelative(
             self.arena.alloc(self.ty(span, hir::TyKind::Path(qpath))),
             self.arena.alloc(hir::PathSegment::new(

compiler/rustc_ast_lowering/src/lib.rs

@@ -55,8 +55,8 @@ use rustc_errors::{DiagArgFromDisplay, DiagCtxtHandle, StashKey};
 use rustc_hir::def::{DefKind, LifetimeRes, Namespace, PartialRes, PerNS, Res};
 use rustc_hir::def_id::{CRATE_DEF_ID, LOCAL_CRATE, LocalDefId, LocalDefIdMap};
 use rustc_hir::{
-    self as hir, ConstArg, GenericArg, HirId, ItemLocalMap, MissingLifetimeKind, ParamName,
-    TraitCandidate,
+    self as hir, ConstArg, GenericArg, HirId, ItemLocalMap, LangItem, MissingLifetimeKind,
+    ParamName, TraitCandidate,
 };
 use rustc_index::{Idx, IndexSlice, IndexVec};
 use rustc_macros::extension;
@@ -765,8 +765,13 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         res
     }
 
-    fn make_lang_item_qpath(&mut self, lang_item: hir::LangItem, span: Span) -> hir::QPath<'hir> {
-        hir::QPath::Resolved(None, self.make_lang_item_path(lang_item, span, None))
+    fn make_lang_item_qpath(
+        &mut self,
+        lang_item: hir::LangItem,
+        span: Span,
+        args: Option<&'hir hir::GenericArgs<'hir>>,
+    ) -> hir::QPath<'hir> {
+        hir::QPath::Resolved(None, self.make_lang_item_path(lang_item, span, args))
     }
 
     fn make_lang_item_path(
@@ -1277,6 +1282,32 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                 let lifetime = self.lower_lifetime(&region);
                 hir::TyKind::Ref(lifetime, self.lower_mt(mt, itctx))
             }
+            TyKind::PinnedRef(region, mt) => {
+                let region = region.unwrap_or_else(|| {
+                    let id = if let Some(LifetimeRes::ElidedAnchor { start, end }) =
+                        self.resolver.get_lifetime_res(t.id)
+                    {
+                        debug_assert_eq!(start.plus(1), end);
+                        start
+                    } else {
+                        self.next_node_id()
+                    };
+                    let span = self.tcx.sess.source_map().start_point(t.span).shrink_to_hi();
+                    Lifetime { ident: Ident::new(kw::UnderscoreLifetime, span), id }
+                });
+                let lifetime = self.lower_lifetime(&region);
+                let kind = hir::TyKind::Ref(lifetime, self.lower_mt(mt, itctx));
+                let span = self.lower_span(t.span);
+                let arg = hir::Ty { kind, span, hir_id: self.next_id() };
+                let args = self.arena.alloc(hir::GenericArgs {
+                    args: self.arena.alloc([hir::GenericArg::Type(self.arena.alloc(arg))]),
+                    constraints: &[],
+                    parenthesized: hir::GenericArgsParentheses::No,
+                    span_ext: span,
+                });
+                let path = self.make_lang_item_qpath(LangItem::Pin, span, Some(args));
+                hir::TyKind::Path(path)
+            }
             TyKind::BareFn(f) => {
                 let generic_params = self.lower_lifetime_binder(t.id, &f.generic_params);
                 hir::TyKind::BareFn(self.arena.alloc(hir::BareFnTy {
@@ -1845,10 +1876,14 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                     // Given we are only considering `ImplicitSelf` types, we needn't consider
                     // the case where we have a mutable pattern to a reference as that would
                     // no longer be an `ImplicitSelf`.
-                    TyKind::Ref(_, mt) if mt.ty.kind.is_implicit_self() => match mt.mutbl {
-                        hir::Mutability::Not => hir::ImplicitSelfKind::RefImm,
-                        hir::Mutability::Mut => hir::ImplicitSelfKind::RefMut,
-                    },
+                    TyKind::Ref(_, mt) | TyKind::PinnedRef(_, mt)
+                        if mt.ty.kind.is_implicit_self() =>
+                    {
+                        match mt.mutbl {
+                            hir::Mutability::Not => hir::ImplicitSelfKind::RefImm,
+                            hir::Mutability::Mut => hir::ImplicitSelfKind::RefMut,
+                        }
+                    }
                     _ => hir::ImplicitSelfKind::None,
                 }
             }),

compiler/rustc_ast_lowering/src/lifetime_collector.rs

@@ -95,7 +95,7 @@ impl<'ast> Visitor<'ast> for LifetimeCollectVisitor<'ast> {
                 visit::walk_ty(self, t);
                 self.current_binders.pop();
             }
-            TyKind::Ref(None, _) => {
+            TyKind::Ref(None, _) | TyKind::PinnedRef(None, _) => {
                 self.record_elided_anchor(t.id, t.span);
                 visit::walk_ty(self, t);
             }

compiler/rustc_ast_passes/src/feature_gate.rs

@@ -546,6 +546,7 @@ pub fn check_crate(krate: &ast::Crate, sess: &Session, features: &Features) {
     gate_all!(mut_ref, "mutable by-reference bindings are experimental");
     gate_all!(global_registration, "global registration is experimental");
     gate_all!(return_type_notation, "return type notation is experimental");
+    gate_all!(pin_ergonomics, "pinned reference syntax is experimental");
 
     if !visitor.features.never_patterns {
         if let Some(spans) = spans.get(&sym::never_patterns) {

compiler/rustc_ast_pretty/src/pprust/state.rs

@@ -1163,6 +1163,12 @@ impl<'a> State<'a> {
                 self.print_opt_lifetime(lifetime);
                 self.print_mt(mt, false);
             }
+            ast::TyKind::PinnedRef(lifetime, mt) => {
+                self.word("&");
+                self.print_opt_lifetime(lifetime);
+                self.word("pin ");
+                self.print_mt(mt, true);
+            }
             ast::TyKind::Never => {
                 self.word("!");
             }

compiler/rustc_hir/src/hir.rs

@@ -1,10 +1,9 @@
 use std::fmt;
 
-use rustc_ast as ast;
 use rustc_ast::util::parser::ExprPrecedence;
 use rustc_ast::{
-    Attribute, FloatTy, InlineAsmOptions, InlineAsmTemplatePiece, IntTy, Label, LitKind,
-    TraitObjectSyntax, UintTy,
+    self as ast, Attribute, FloatTy, InlineAsmOptions, InlineAsmTemplatePiece, IntTy, Label,
+    LitKind, TraitObjectSyntax, UintTy,
 };
 pub use rustc_ast::{
     BinOp, BinOpKind, BindingMode, BorrowKind, ByRef, CaptureBy, ImplPolarity, IsAuto, Movability,

compiler/rustc_hir_analysis/messages.ftl

@@ -68,18 +68,21 @@ hir_analysis_closure_implicit_hrtb = implicit types in closure signatures are fo
 hir_analysis_cmse_call_generic =
     function pointers with the `"C-cmse-nonsecure-call"` ABI cannot contain generics in their type
 
-hir_analysis_cmse_call_inputs_stack_spill =
-    arguments for `"C-cmse-nonsecure-call"` function too large to pass via registers
+hir_analysis_cmse_entry_generic =
+    functions with the `"C-cmse-nonsecure-entry"` ABI cannot contain generics in their type
+
+hir_analysis_cmse_inputs_stack_spill =
+    arguments for `"{$abi_name}"` function too large to pass via registers
     .label = {$plural ->
         [false] this argument doesn't
         *[true] these arguments don't
     } fit in the available registers
-    .note = functions with the `"C-cmse-nonsecure-call"` ABI must pass all their arguments via the 4 32-bit available argument registers
+    .note = functions with the `"{$abi_name}"` ABI must pass all their arguments via the 4 32-bit available argument registers
 
-hir_analysis_cmse_call_output_stack_spill =
-    return value of `"C-cmse-nonsecure-call"` function too large to pass via registers
+hir_analysis_cmse_output_stack_spill =
+    return value of `"{$abi_name}"` function too large to pass via registers
     .label = this type doesn't fit in the available registers
-    .note1 = functions with the `"C-cmse-nonsecure-call"` ABI must pass their result via the available return registers
+    .note1 = functions with the `"{$abi_name}"` ABI must pass their result via the available return registers
     .note2 = the result must either be a (transparently wrapped) i64, u64 or f64, or be at most 4 bytes in size
 
 hir_analysis_coerce_unsized_may = the trait `{$trait_name}` may only be implemented for a coercion between structures

compiler/rustc_hir_analysis/src/check/wfcheck.rs

@@ -531,7 +531,7 @@ fn check_gat_where_clauses(tcx: TyCtxt<'_>, trait_def_id: LocalDefId) {
         debug!(?required_bounds);
         let param_env = tcx.param_env(gat_def_id);
 
-        let mut unsatisfied_bounds: Vec<_> = required_bounds
+        let unsatisfied_bounds: Vec<_> = required_bounds
             .into_iter()
             .filter(|clause| match clause.kind().skip_binder() {
                 ty::ClauseKind::RegionOutlives(ty::OutlivesPredicate(a, b)) => {
@@ -552,9 +552,6 @@ fn check_gat_where_clauses(tcx: TyCtxt<'_>, trait_def_id: LocalDefId) {
             .map(|clause| clause.to_string())
             .collect();
 
-        // We sort so that order is predictable
-        unsatisfied_bounds.sort();
-
         if !unsatisfied_bounds.is_empty() {
             let plural = pluralize!(unsatisfied_bounds.len());
             let suggestion = format!(

compiler/rustc_hir_analysis/src/coherence/inherent_impls_overlap.rs

@@ -319,9 +319,7 @@ impl<'tcx> InherentOverlapChecker<'tcx> {
             // List of connected regions is built. Now, run the overlap check
             // for each pair of impl blocks in the same connected region.
             for region in connected_regions.into_iter().flatten() {
-                let mut impl_blocks =
-                    region.impl_blocks.into_iter().collect::<SmallVec<[usize; 8]>>();
-                impl_blocks.sort_unstable();
+                let impl_blocks = region.impl_blocks.into_iter().collect::<SmallVec<[usize; 8]>>();
                 for (i, &impl1_items_idx) in impl_blocks.iter().enumerate() {
                     let &(&impl1_def_id, impl_items1) = &impls_items[impl1_items_idx];
                     res = res.and(self.check_for_duplicate_items_in_impl(impl1_def_id));

compiler/rustc_hir_analysis/src/errors.rs

@@ -1627,23 +1627,25 @@ pub(crate) struct InvalidReceiverTy<'tcx> {
 pub(crate) struct EffectsWithoutNextSolver;
 
 #[derive(Diagnostic)]
-#[diag(hir_analysis_cmse_call_inputs_stack_spill, code = E0798)]
+#[diag(hir_analysis_cmse_inputs_stack_spill, code = E0798)]
 #[note]
-pub(crate) struct CmseCallInputsStackSpill {
+pub(crate) struct CmseInputsStackSpill {
     #[primary_span]
     #[label]
     pub span: Span,
     pub plural: bool,
+    pub abi_name: &'static str,
 }
 
 #[derive(Diagnostic)]
-#[diag(hir_analysis_cmse_call_output_stack_spill, code = E0798)]
+#[diag(hir_analysis_cmse_output_stack_spill, code = E0798)]
 #[note(hir_analysis_note1)]
 #[note(hir_analysis_note2)]
-pub(crate) struct CmseCallOutputStackSpill {
+pub(crate) struct CmseOutputStackSpill {
     #[primary_span]
     #[label]
     pub span: Span,
+    pub abi_name: &'static str,
 }
 
 #[derive(Diagnostic)]
@@ -1659,3 +1661,10 @@ pub(crate) struct BadReturnTypeNotation {
     #[primary_span]
     pub span: Span,
 }
+
+#[derive(Diagnostic)]
+#[diag(hir_analysis_cmse_entry_generic, code = E0798)]
+pub(crate) struct CmseEntryGeneric {
+    #[primary_span]
+    pub span: Span,
+}