Rollup of 11 pull requests

compiler/rustc_codegen_ssa/src/mir/intrinsic.rs

@@ -524,8 +524,19 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                         };
 
                         let ty = substs.type_at(0);
-                        if int_type_width_signed(ty, bx.tcx()).is_some() {
-                            bx.atomic_rmw(atom_op, args[0].immediate(), args[1].immediate(), order)
+                        if int_type_width_signed(ty, bx.tcx()).is_some()
+                            || (ty.is_unsafe_ptr() && op == "xchg")
+                        {
+                            let mut ptr = args[0].immediate();
+                            let mut val = args[1].immediate();
+                            if ty.is_unsafe_ptr() {
+                                // Some platforms do not support atomic operations on pointers,
+                                // so we cast to integer first.
+                                let ptr_llty = bx.type_ptr_to(bx.type_isize());
+                                ptr = bx.pointercast(ptr, ptr_llty);
+                                val = bx.ptrtoint(val, bx.type_isize());
+                            }
+                            bx.atomic_rmw(atom_op, ptr, val, order)
                         } else {
                             return invalid_monomorphization(ty);
                         }

compiler/rustc_middle/src/hir/place.rs

@@ -17,13 +17,13 @@ use rustc_target::abi::VariantIdx;
     HashStable
 )]
 pub enum PlaceBase {
-    /// A temporary variable
+    /// A temporary variable.
     Rvalue,
-    /// A named `static` item
+    /// A named `static` item.
     StaticItem,
-    /// A named local variable
+    /// A named local variable.
     Local(HirId),
-    /// An upvar referenced by closure env
+    /// An upvar referenced by closure env.
     Upvar(ty::UpvarId),
 }
 
@@ -40,7 +40,7 @@ pub enum PlaceBase {
     HashStable
 )]
 pub enum ProjectionKind {
-    /// A dereference of a pointer, reference or `Box<T>` of the given type
+    /// A dereference of a pointer, reference or `Box<T>` of the given type.
     Deref,
 
     /// `B.F` where `B` is the base expression and `F` is
@@ -71,16 +71,16 @@ pub enum ProjectionKind {
     HashStable
 )]
 pub struct Projection<'tcx> {
-    /// Type after the projection is being applied.
+    /// Type after the projection is applied.
     pub ty: Ty<'tcx>,
 
-    /// Defines the type of access
+    /// Defines the kind of access made by the projection.
     pub kind: ProjectionKind,
 }
 
 /// A `Place` represents how a value is located in memory.
 ///
-/// This is an HIR version of `mir::Place`
+/// This is an HIR version of [`rustc_middle::mir::Place`].
 #[derive(Clone, Debug, PartialEq, Eq, Hash, TyEncodable, TyDecodable, TypeFoldable, HashStable)]
 pub struct Place<'tcx> {
     /// The type of the `PlaceBase`
@@ -93,13 +93,13 @@ pub struct Place<'tcx> {
 
 /// A `PlaceWithHirId` represents how a value is located in memory.
 ///
-/// This is an HIR version of `mir::Place`
+/// This is an HIR version of [`rustc_middle::mir::Place`].
 #[derive(Clone, Debug, PartialEq, Eq, Hash, TyEncodable, TyDecodable, TypeFoldable, HashStable)]
 pub struct PlaceWithHirId<'tcx> {
     /// `HirId` of the expression or pattern producing this value.
     pub hir_id: HirId,
 
-    /// Information about the `Place`
+    /// Information about the `Place`.
     pub place: Place<'tcx>,
 }
 

compiler/rustc_middle/src/ty/sty.rs

@@ -88,6 +88,8 @@ impl BoundRegionKind {
     }
 }
 
+/// Defines the kinds of types.
+///
 /// N.B., if you change this, you'll probably want to change the corresponding
 /// AST structure in `librustc_ast/ast.rs` as well.
 #[derive(Clone, PartialEq, Eq, PartialOrd, Ord, Hash, TyEncodable, TyDecodable, Debug)]
@@ -110,7 +112,7 @@ pub enum TyKind<'tcx> {
     /// A primitive floating-point type. For example, `f64`.
     Float(ast::FloatTy),
 
-    /// Structures, enumerations and unions.
+    /// Algebraic data types (ADT). For example: structures, enumerations and unions.
     ///
     /// InternalSubsts here, possibly against intuition, *may* contain `Param`s.
     /// That is, even after substitution it is possible that there are type
@@ -170,11 +172,11 @@ pub enum TyKind<'tcx> {
     /// `|a| yield a`.
     Generator(DefId, SubstsRef<'tcx>, hir::Movability),
 
-    /// A type representin the types stored inside a generator.
+    /// A type representing the types stored inside a generator.
     /// This should only appear in GeneratorInteriors.
     GeneratorWitness(Binder<&'tcx List<Ty<'tcx>>>),
 
-    /// The never type `!`
+    /// The never type `!`.
     Never,
 
     /// A tuple type. For example, `(i32, bool)`.

compiler/rustc_mir/src/transform/check_consts/validation.rs

@@ -722,17 +722,16 @@ impl Visitor<'tcx> for Validator<'mir, 'tcx> {
     fn visit_statement(&mut self, statement: &Statement<'tcx>, location: Location) {
         trace!("visit_statement: statement={:?} location={:?}", statement, location);
 
-        match statement.kind {
-            StatementKind::Assign(..) | StatementKind::SetDiscriminant { .. } => {
-                self.super_statement(statement, location);
-            }
+        self.super_statement(statement, location);
 
+        match statement.kind {
             StatementKind::LlvmInlineAsm { .. } => {
-                self.super_statement(statement, location);
                 self.check_op(ops::InlineAsm);
             }
 
-            StatementKind::FakeRead(..)
+            StatementKind::Assign(..)
+            | StatementKind::SetDiscriminant { .. }
+            | StatementKind::FakeRead(..)
             | StatementKind::StorageLive(_)
             | StatementKind::StorageDead(_)
             | StatementKind::Retag { .. }

compiler/rustc_resolve/src/late.rs

@@ -29,7 +29,7 @@ use rustc_span::Span;
 use smallvec::{smallvec, SmallVec};
 
 use rustc_span::source_map::{respan, Spanned};
-use std::collections::BTreeSet;
+use std::collections::{hash_map::Entry, BTreeSet};
 use std::mem::{replace, take};
 use tracing::debug;
 
@@ -953,8 +953,8 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
                             });
                         };
 
-                        for item in trait_items {
-                            this.with_trait_items(trait_items, |this| {
+                        this.with_trait_items(trait_items, |this| {
+                            for item in trait_items {
                                 match &item.kind {
                                     AssocItemKind::Const(_, ty, default) => {
                                         this.visit_ty(ty);
@@ -983,8 +983,8 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
                                         panic!("unexpanded macro in resolve!")
                                     }
                                 };
-                            });
-                        }
+                            }
+                        });
                     });
                 });
             }
@@ -1060,36 +1060,29 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
                 continue;
             }
 
-            let def_kind = match param.kind {
-                GenericParamKind::Type { .. } => DefKind::TyParam,
-                GenericParamKind::Const { .. } => DefKind::ConstParam,
-                _ => unreachable!(),
-            };
-
             let ident = param.ident.normalize_to_macros_2_0();
             debug!("with_generic_param_rib: {}", param.id);
 
-            if seen_bindings.contains_key(&ident) {
-                let span = seen_bindings.get(&ident).unwrap();
-                let err = ResolutionError::NameAlreadyUsedInParameterList(ident.name, *span);
-                self.report_error(param.ident.span, err);
+            match seen_bindings.entry(ident) {
+                Entry::Occupied(entry) => {
+                    let span = *entry.get();
+                    let err = ResolutionError::NameAlreadyUsedInParameterList(ident.name, span);
+                    self.report_error(param.ident.span, err);
+                }
+                Entry::Vacant(entry) => {
+                    entry.insert(param.ident.span);
+                }
             }
-            seen_bindings.entry(ident).or_insert(param.ident.span);
 
             // Plain insert (no renaming).
-            let res = Res::Def(def_kind, self.r.local_def_id(param.id).to_def_id());
-
-            match param.kind {
-                GenericParamKind::Type { .. } => {
-                    function_type_rib.bindings.insert(ident, res);
-                    self.r.record_partial_res(param.id, PartialRes::new(res));
-                }
-                GenericParamKind::Const { .. } => {
-                    function_value_rib.bindings.insert(ident, res);
-                    self.r.record_partial_res(param.id, PartialRes::new(res));
-                }
+            let (rib, def_kind) = match param.kind {
+                GenericParamKind::Type { .. } => (&mut function_type_rib, DefKind::TyParam),
+                GenericParamKind::Const { .. } => (&mut function_value_rib, DefKind::ConstParam),
                 _ => unreachable!(),
-            }
+            };
+            let res = Res::Def(def_kind, self.r.local_def_id(param.id).to_def_id());
+            self.r.record_partial_res(param.id, PartialRes::new(res));
+            rib.bindings.insert(ident, res);
         }
 
         self.ribs[ValueNS].push(function_value_rib);
@@ -1778,7 +1771,6 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
             path
         );
         let ns = source.namespace();
-        let is_expected = &|res| source.is_expected(res);
 
         let report_errors = |this: &mut Self, res: Option<Res>| {
             if this.should_report_errs() {
@@ -1881,7 +1873,8 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
             crate_lint,
         ) {
             Ok(Some(partial_res)) if partial_res.unresolved_segments() == 0 => {
-                if is_expected(partial_res.base_res()) || partial_res.base_res() == Res::Err {
+                if source.is_expected(partial_res.base_res()) || partial_res.base_res() == Res::Err
+                {
                     partial_res
                 } else {
                     report_errors(self, Some(partial_res.base_res()))
@@ -1898,11 +1891,11 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
                     self.r.trait_map.insert(id, traits);
                 }
 
-                let mut std_path = vec![Segment::from_ident(Ident::with_dummy_span(sym::std))];
-
-                std_path.extend(path);
-
                 if self.r.primitive_type_table.primitive_types.contains_key(&path[0].ident.name) {
+                    let mut std_path = Vec::with_capacity(1 + path.len());
+
+                    std_path.push(Segment::from_ident(Ident::with_dummy_span(sym::std)));
+                    std_path.extend(path);
                     if let PathResult::Module(_) | PathResult::NonModule(_) =
                         self.resolve_path(&std_path, Some(ns), false, span, CrateLint::No)
                     {
@@ -1983,7 +1976,7 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
     ) -> Result<Option<PartialRes>, Spanned<ResolutionError<'a>>> {
         let mut fin_res = None;
 
-        for (i, ns) in [primary_ns, TypeNS, ValueNS].iter().cloned().enumerate() {
+        for (i, &ns) in [primary_ns, TypeNS, ValueNS].iter().enumerate() {
             if i == 0 || ns != primary_ns {
                 match self.resolve_qpath(id, qself, path, ns, span, crate_lint)? {
                     Some(partial_res)
@@ -1993,7 +1986,7 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
                     }
                     partial_res => {
                         if fin_res.is_none() {
-                            fin_res = partial_res
+                            fin_res = partial_res;
                         }
                     }
                 }

compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs

@@ -254,27 +254,21 @@ fn suggest_restriction(
         let pred = trait_ref.without_const().to_predicate(tcx).to_string();
         let pred = pred.replace(&impl_trait_str, &type_param_name);
         let mut sugg = vec![
+            // Find the last of the generic parameters contained within the span of
+            // the generics
             match generics
                 .params
                 .iter()
-                .filter(|p| match p.kind {
-                    hir::GenericParamKind::Type {
-                        synthetic: Some(hir::SyntheticTyParamKind::ImplTrait),
-                        ..
-                    } => false,
-                    _ => true,
-                })
-                .last()
+                .map(|p| p.bounds_span().unwrap_or(p.span))
+                .filter(|&span| generics.span.contains(span) && span.desugaring_kind().is_none())
+                .max_by_key(|span| span.hi())
             {
                 // `fn foo(t: impl Trait)`
                 //        ^ suggest `<T: Trait>` here
                 None => (generics.span, format!("<{}>", type_param)),
                 // `fn foo<A>(t: impl Trait)`
                 //        ^^^ suggest `<A, T: Trait>` here
-                Some(param) => (
-                    param.bounds_span().unwrap_or(param.span).shrink_to_hi(),
-                    format!(", {}", type_param),
-                ),
+                Some(span) => (span.shrink_to_hi(), format!(", {}", type_param)),
             },
             // `fn foo(t: impl Trait)`
             //                       ^ suggest `where <T as Trait>::A: Bound`

compiler/rustc_typeck/src/check/_match.rs

@@ -31,7 +31,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             _ => (false, false, false),
         };
 
-        // Type check the descriminant and get its type.
+        // Type check the discriminant and get its type.
         let scrutinee_ty = if force_scrutinee_bool {
             // Here we want to ensure:
             //

compiler/rustc_typeck/src/check/op.rs

@@ -503,8 +503,14 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             if !self.tcx.has_typeck_results(def_id) {
                 return false;
             }
-            // We're emitting a suggestion, so we can just ignore regions
-            let fn_sig = self.tcx.fn_sig(def_id).skip_binder();
+            // FIXME: Instead of exiting early when encountering bound vars in
+            // the function signature, consider keeping the binder here and
+            // propagating it downwards.
+            let fn_sig = if let Some(fn_sig) = self.tcx.fn_sig(def_id).no_bound_vars() {
+                fn_sig
+            } else {
+                return false;
+            };
 
             let other_ty = if let FnDef(def_id, _) = *other_ty.kind() {
                 if !self.tcx.has_typeck_results(def_id) {

library/core/src/sync/atomic.rs

@@ -1040,8 +1040,16 @@ impl<T> AtomicPtr<T> {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[cfg(target_has_atomic = "ptr")]
     pub fn swap(&self, ptr: *mut T, order: Ordering) -> *mut T {
+        #[cfg(bootstrap)]
         // SAFETY: data races are prevented by atomic intrinsics.
-        unsafe { atomic_swap(self.p.get() as *mut usize, ptr as usize, order) as *mut T }
+        unsafe {
+            atomic_swap(self.p.get() as *mut usize, ptr as usize, order) as *mut T
+        }
+        #[cfg(not(bootstrap))]
+        // SAFETY: data races are prevented by atomic intrinsics.
+        unsafe {
+            atomic_swap(self.p.get(), ptr, order)
+        }
     }
 
     /// Stores a value into the pointer if the current value is the same as the `current` value.

library/std/src/primitive_docs.rs

@@ -478,8 +478,10 @@ mod prim_unit {}
 #[stable(feature = "rust1", since = "1.0.0")]
 mod prim_pointer {}
 
+#[doc(alias = "[]")]
+#[doc(alias = "[T;N]")] // unfortunately, rustdoc doesn't have fuzzy search for aliases
+#[doc(alias = "[T; N]")]
 #[doc(primitive = "array")]
-//
 /// A fixed-size array, denoted `[T; N]`, for the element type, `T`, and the
 /// non-negative compile-time constant size, `N`.
 ///

src/bootstrap/install.rs

@@ -73,12 +73,7 @@ fn install_sh(
     let docdir_default = datadir_default.join("doc/rust");
     let libdir_default = PathBuf::from("lib");
     let mandir_default = datadir_default.join("man");
-    let prefix = builder.config.prefix.as_ref().map_or(prefix_default, |p| {
-        fs::create_dir_all(p)
-            .unwrap_or_else(|err| panic!("could not create {}: {}", p.display(), err));
-        fs::canonicalize(p)
-            .unwrap_or_else(|err| panic!("could not canonicalize {}: {}", p.display(), err))
-    });
+    let prefix = builder.config.prefix.as_ref().unwrap_or(&prefix_default);
     let sysconfdir = builder.config.sysconfdir.as_ref().unwrap_or(&sysconfdir_default);
     let datadir = builder.config.datadir.as_ref().unwrap_or(&datadir_default);
     let docdir = builder.config.docdir.as_ref().unwrap_or(&docdir_default);
@@ -103,6 +98,13 @@ fn install_sh(
     let libdir = add_destdir(&libdir, &destdir);
     let mandir = add_destdir(&mandir, &destdir);
 
+    let prefix = {
+        fs::create_dir_all(&prefix)
+            .unwrap_or_else(|err| panic!("could not create {}: {}", prefix.display(), err));
+        fs::canonicalize(&prefix)
+            .unwrap_or_else(|err| panic!("could not canonicalize {}: {}", prefix.display(), err))
+    };
+
     let empty_dir = builder.out.join("tmp/empty_dir");
 
     t!(fs::create_dir_all(&empty_dir));