Rollup of 11 pull requests

compiler/rustc_arena/src/lib.rs

@@ -618,7 +618,7 @@ impl DroplessArena {
 /// - Types that are `!Copy` and `Drop`: these must be specified in the
 ///   arguments. The `TypedArena` will be used for them.
 ///
-#[rustc_macro_transparency = "semitransparent"]
+#[rustc_macro_transparency = "semiopaque"]
 pub macro declare_arena([$($a:tt $name:ident: $ty:ty,)*]) {
     #[derive(Default)]
     pub struct Arena<'tcx> {

compiler/rustc_ast_lowering/src/lib.rs

@@ -1986,8 +1986,9 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         let (name, kind) = self.lower_generic_param_kind(param, source);
 
         let hir_id = self.lower_node_id(param.id);
-        self.lower_attrs(hir_id, &param.attrs, param.span(), Target::Param);
-        hir::GenericParam {
+        let param_attrs = &param.attrs;
+        let param_span = param.span();
+        let param = hir::GenericParam {
             hir_id,
             def_id: self.local_def_id(param.id),
             name,
@@ -1996,7 +1997,9 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
             kind,
             colon_span: param.colon_span.map(|s| self.lower_span(s)),
             source,
-        }
+        };
+        self.lower_attrs(hir_id, param_attrs, param_span, Target::from_generic_param(&param));
+        param
     }
 
     fn lower_generic_param_kind(

compiler/rustc_attr_parsing/src/attributes/stability.rs

@@ -1,6 +1,7 @@
 use std::num::NonZero;
 
 use rustc_errors::ErrorGuaranteed;
+use rustc_hir::target::GenericParamKind;
 use rustc_hir::{
     DefaultBodyStability, MethodKind, PartialConstStability, Stability, StabilityLevel,
     StableSince, Target, UnstableReason, VERSION_PLACEHOLDER,
@@ -43,7 +44,7 @@ const ALLOWED_TARGETS: AllowedTargets = AllowedTargets::AllowList(&[
     Allow(Target::TyAlias),
     Allow(Target::Variant),
     Allow(Target::Field),
-    Allow(Target::Param),
+    Allow(Target::GenericParam { kind: GenericParamKind::Type, has_default: true }),
     Allow(Target::Static),
     Allow(Target::ForeignFn),
     Allow(Target::ForeignStatic),

compiler/rustc_attr_parsing/src/attributes/transparency.rs

@@ -15,7 +15,7 @@ impl<S: Stage> SingleAttributeParser<S> for TransparencyParser {
     });
     const ALLOWED_TARGETS: AllowedTargets = AllowedTargets::AllowList(&[Allow(Target::MacroDef)]);
     const TEMPLATE: AttributeTemplate =
-        template!(NameValueStr: ["transparent", "semitransparent", "opaque"]);
+        template!(NameValueStr: ["transparent", "semiopaque", "opaque"]);
 
     fn convert(cx: &mut AcceptContext<'_, '_, S>, args: &ArgParser) -> Option<AttributeKind> {
         let Some(nv) = args.name_value() else {
@@ -24,12 +24,12 @@ impl<S: Stage> SingleAttributeParser<S> for TransparencyParser {
         };
         match nv.value_as_str() {
             Some(sym::transparent) => Some(Transparency::Transparent),
-            Some(sym::semiopaque | sym::semitransparent) => Some(Transparency::SemiOpaque),
+            Some(sym::semiopaque) => Some(Transparency::SemiOpaque),
             Some(sym::opaque) => Some(Transparency::Opaque),
             Some(_) => {
                 cx.expected_specific_argument_strings(
                     nv.value_span,
-                    &[sym::transparent, sym::semitransparent, sym::opaque],
+                    &[sym::transparent, sym::semiopaque, sym::opaque],
                 );
                 None
             }

compiler/rustc_attr_parsing/src/target_checking.rs

@@ -310,5 +310,29 @@ pub(crate) const ALL_TARGETS: &'static [Policy] = {
         Allow(Target::Crate),
         Allow(Target::Delegation { mac: false }),
         Allow(Target::Delegation { mac: true }),
+        Allow(Target::GenericParam {
+            kind: rustc_hir::target::GenericParamKind::Const,
+            has_default: false,
+        }),
+        Allow(Target::GenericParam {
+            kind: rustc_hir::target::GenericParamKind::Const,
+            has_default: true,
+        }),
+        Allow(Target::GenericParam {
+            kind: rustc_hir::target::GenericParamKind::Lifetime,
+            has_default: false,
+        }),
+        Allow(Target::GenericParam {
+            kind: rustc_hir::target::GenericParamKind::Lifetime,
+            has_default: true,
+        }),
+        Allow(Target::GenericParam {
+            kind: rustc_hir::target::GenericParamKind::Type,
+            has_default: false,
+        }),
+        Allow(Target::GenericParam {
+            kind: rustc_hir::target::GenericParamKind::Type,
+            has_default: true,
+        }),
     ]
 };

compiler/rustc_codegen_cranelift/example/mini_core.rs

@@ -744,43 +744,43 @@ unsafe extern "C" {
 pub struct VaList<'a>(&'a mut VaListImpl);
 
 #[rustc_builtin_macro]
-#[rustc_macro_transparency = "semitransparent"]
+#[rustc_macro_transparency = "semiopaque"]
 pub macro stringify($($t:tt)*) {
     /* compiler built-in */
 }
 
 #[rustc_builtin_macro]
-#[rustc_macro_transparency = "semitransparent"]
+#[rustc_macro_transparency = "semiopaque"]
 pub macro file() {
     /* compiler built-in */
 }
 
 #[rustc_builtin_macro]
-#[rustc_macro_transparency = "semitransparent"]
+#[rustc_macro_transparency = "semiopaque"]
 pub macro line() {
     /* compiler built-in */
 }
 
 #[rustc_builtin_macro]
-#[rustc_macro_transparency = "semitransparent"]
+#[rustc_macro_transparency = "semiopaque"]
 pub macro cfg() {
     /* compiler built-in */
 }
 
 #[rustc_builtin_macro]
-#[rustc_macro_transparency = "semitransparent"]
+#[rustc_macro_transparency = "semiopaque"]
 pub macro asm() {
     /* compiler built-in */
 }
 
 #[rustc_builtin_macro]
-#[rustc_macro_transparency = "semitransparent"]
+#[rustc_macro_transparency = "semiopaque"]
 pub macro global_asm() {
     /* compiler built-in */
 }
 
 #[rustc_builtin_macro]
-#[rustc_macro_transparency = "semitransparent"]
+#[rustc_macro_transparency = "semiopaque"]
 pub macro naked_asm() {
     /* compiler built-in */
 }

compiler/rustc_codegen_cranelift/src/global_asm.rs

@@ -233,7 +233,7 @@ pub(crate) fn compile_global_asm(
                 #![allow(internal_features)]
                 #![no_core]
                 #[rustc_builtin_macro]
-                #[rustc_macro_transparency = "semitransparent"]
+                #[rustc_macro_transparency = "semiopaque"]
                 macro global_asm() { /* compiler built-in */ }
                 global_asm!(r###"
                 "####,

compiler/rustc_codegen_gcc/example/mini_core.rs

@@ -748,25 +748,25 @@ extern "C" {
 pub struct VaList<'a>(&'a mut VaListImpl);
 
 #[rustc_builtin_macro]
-#[rustc_macro_transparency = "semitransparent"]
+#[rustc_macro_transparency = "semiopaque"]
 pub macro stringify($($t:tt)*) {
     /* compiler built-in */
 }
 
 #[rustc_builtin_macro]
-#[rustc_macro_transparency = "semitransparent"]
+#[rustc_macro_transparency = "semiopaque"]
 pub macro file() {
     /* compiler built-in */
 }
 
 #[rustc_builtin_macro]
-#[rustc_macro_transparency = "semitransparent"]
+#[rustc_macro_transparency = "semiopaque"]
 pub macro line() {
     /* compiler built-in */
 }
 
 #[rustc_builtin_macro]
-#[rustc_macro_transparency = "semitransparent"]
+#[rustc_macro_transparency = "semiopaque"]
 pub macro cfg() {
     /* compiler built-in */
 }

compiler/rustc_feature/src/unstable.rs

@@ -233,8 +233,6 @@ declare_features! (
     (internal, link_cfg, "1.14.0", None),
     /// Allows using `?Trait` trait bounds in more contexts.
     (internal, more_maybe_bounds, "1.82.0", None),
-    /// Allows the `multiple_supertrait_upcastable` lint.
-    (unstable, multiple_supertrait_upcastable, "1.69.0", None),
     /// Allow negative trait bounds. This is an internal-only feature for testing the trait solver!
     (internal, negative_bounds, "1.71.0", None),
     /// Set the maximum pattern complexity allowed (not limited by default).
@@ -569,6 +567,8 @@ declare_features! (
     (unstable, more_qualified_paths, "1.54.0", Some(86935)),
     /// The `movrs` target feature on x86.
     (unstable, movrs_target_feature, "1.88.0", Some(137976)),
+    /// Allows the `multiple_supertrait_upcastable` lint.
+    (unstable, multiple_supertrait_upcastable, "1.69.0", Some(150833)),
     /// Allows the `#[must_not_suspend]` attribute.
     (unstable, must_not_suspend, "1.57.0", Some(83310)),
     /// Allows `mut ref` and `mut ref mut` identifier patterns.

compiler/rustc_hir/src/hir.rs

@@ -2625,6 +2625,12 @@ impl Expr<'_> {
                 // them being used only for its side-effects.
                 base.can_have_side_effects()
             }
+            ExprKind::Binary(_, lhs, rhs) => {
+                // This isn't exactly true for all `Binary`, but we are using this
+                // method exclusively for diagnostics and there's a *cultural* pressure against
+                // them being used only for its side-effects.
+                lhs.can_have_side_effects() || rhs.can_have_side_effects()
+            }
             ExprKind::Struct(_, fields, init) => {
                 let init_side_effects = match init {
                     StructTailExpr::Base(init) => init.can_have_side_effects(),
@@ -2647,13 +2653,13 @@ impl Expr<'_> {
                 },
                 args,
             ) => args.iter().any(|arg| arg.can_have_side_effects()),
+            ExprKind::Repeat(arg, _) => arg.can_have_side_effects(),
             ExprKind::If(..)
             | ExprKind::Match(..)
             | ExprKind::MethodCall(..)
             | ExprKind::Call(..)
             | ExprKind::Closure { .. }
             | ExprKind::Block(..)
-            | ExprKind::Repeat(..)
             | ExprKind::Break(..)
             | ExprKind::Continue(..)
             | ExprKind::Ret(..)
@@ -2664,7 +2670,6 @@ impl Expr<'_> {
             | ExprKind::InlineAsm(..)
             | ExprKind::AssignOp(..)
             | ExprKind::ConstBlock(..)
-            | ExprKind::Binary(..)
             | ExprKind::Yield(..)
             | ExprKind::DropTemps(..)
             | ExprKind::Err(_) => true,

compiler/rustc_hir/src/lib.rs

@@ -32,7 +32,7 @@ pub mod lints;
 pub mod pat_util;
 mod stability;
 mod stable_hash_impls;
-mod target;
+pub mod target;
 pub mod weak_lang_items;
 
 #[cfg(test)]

compiler/rustc_mir_dataflow/src/move_paths/mod.rs

@@ -177,8 +177,9 @@ pub struct MoveData<'tcx> {
     pub rev_lookup: MovePathLookup<'tcx>,
     pub inits: IndexVec<InitIndex, Init>,
     /// Each Location `l` is mapped to the Inits that are effects
-    /// of executing the code at `l`.
-    pub init_loc_map: LocationMap<SmallVec<[InitIndex; 4]>>,
+    /// of executing the code at `l`. Only very rarely (e.g. inline asm)
+    /// is there more than one Init at any `l`.
+    pub init_loc_map: LocationMap<SmallVec<[InitIndex; 1]>>,
     pub init_path_map: IndexVec<MovePathIndex, SmallVec<[InitIndex; 4]>>,
 }
 

compiler/rustc_span/src/symbol.rs

@@ -2041,7 +2041,6 @@ symbols! {
         self_in_typedefs,
         self_struct_ctor,
         semiopaque,
-        semitransparent,
         sha2,
         sha3,
         sha512_sm_x86,

library/core/src/clone.rs

@@ -285,7 +285,7 @@ pub const unsafe trait TrivialClone: [const] Clone {}
 /// Derive macro generating an impl of the trait `Clone`.
 #[rustc_builtin_macro]
 #[stable(feature = "builtin_macro_prelude", since = "1.38.0")]
-#[allow_internal_unstable(core_intrinsics, derive_clone_copy, trivial_clone)]
+#[allow_internal_unstable(core_intrinsics, derive_clone_copy_internals, trivial_clone)]
 pub macro Clone($item:item) {
     /* compiler built-in */
 }
@@ -350,7 +350,7 @@ impl_use_cloned! {
 #[doc(hidden)]
 #[allow(missing_debug_implementations)]
 #[unstable(
-    feature = "derive_clone_copy",
+    feature = "derive_clone_copy_internals",
     reason = "deriving hack, should not be public",
     issue = "none"
 )]
@@ -360,7 +360,7 @@ pub struct AssertParamIsClone<T: Clone + PointeeSized> {
 #[doc(hidden)]
 #[allow(missing_debug_implementations)]
 #[unstable(
-    feature = "derive_clone_copy",
+    feature = "derive_clone_copy_internals",
     reason = "deriving hack, should not be public",
     issue = "none"
 )]

library/core/src/cmp.rs

@@ -351,7 +351,7 @@ pub const trait Eq: [const] PartialEq<Self> + PointeeSized {
 /// Derive macro generating an impl of the trait [`Eq`].
 #[rustc_builtin_macro]
 #[stable(feature = "builtin_macro_prelude", since = "1.38.0")]
-#[allow_internal_unstable(core_intrinsics, derive_eq, structural_match)]
+#[allow_internal_unstable(core_intrinsics, derive_eq_internals, structural_match)]
 #[allow_internal_unstable(coverage_attribute)]
 pub macro Eq($item:item) {
     /* compiler built-in */
@@ -363,7 +363,11 @@ pub macro Eq($item:item) {
 // This struct should never appear in user code.
 #[doc(hidden)]
 #[allow(missing_debug_implementations)]
-#[unstable(feature = "derive_eq", reason = "deriving hack, should not be public", issue = "none")]
+#[unstable(
+    feature = "derive_eq_internals",
+    reason = "deriving hack, should not be public",
+    issue = "none"
+)]
 pub struct AssertParamIsEq<T: Eq + PointeeSized> {
     _field: crate::marker::PhantomData<T>,
 }

library/core/src/iter/traits/double_ended.rs

@@ -334,8 +334,18 @@ pub trait DoubleEndedIterator: Iterator {
     /// ```
     /// let a = [1, 2, 3];
     ///
-    /// assert_eq!(a.iter().rfind(|&&x| x == 2), Some(&2));
+    /// assert_eq!(a.into_iter().rfind(|&x| x == 2), Some(2));
+    /// assert_eq!(a.into_iter().rfind(|&x| x == 5), None);
+    /// ```
     ///
+    /// Iterating over references:
+    ///
+    /// ```
+    /// let a = [1, 2, 3];
+    ///
+    /// // `iter()` yields references i.e. `&i32` and `rfind()` takes a
+    /// // reference to each element.
+    /// assert_eq!(a.iter().rfind(|&&x| x == 2), Some(&2));
     /// assert_eq!(a.iter().rfind(|&&x| x == 5), None);
     /// ```
     ///

library/core/src/iter/traits/iterator.rs

@@ -2862,6 +2862,17 @@ pub trait Iterator {
     /// assert_eq!(a.into_iter().find(|&x| x == 5), None);
     /// ```
     ///
+    /// Iterating over references:
+    ///
+    /// ```
+    /// let a = [1, 2, 3];
+    ///
+    /// // `iter()` yields references i.e. `&i32` and `find()` takes a
+    /// // reference to each element.
+    /// assert_eq!(a.iter().find(|&&x| x == 2), Some(&2));
+    /// assert_eq!(a.iter().find(|&&x| x == 5), None);
+    /// ```
+    ///
     /// Stopping at the first `true`:
     ///
     /// ```

library/core/src/macros/mod.rs

@@ -168,7 +168,7 @@ macro_rules! assert_ne {
 /// ```
 #[unstable(feature = "assert_matches", issue = "82775")]
 #[allow_internal_unstable(panic_internals)]
-#[rustc_macro_transparency = "semitransparent"]
+#[rustc_macro_transparency = "semiopaque"]
 pub macro assert_matches {
     ($left:expr, $(|)? $( $pattern:pat_param )|+ $( if $guard: expr )? $(,)?) => {
         match $left {
@@ -401,7 +401,7 @@ macro_rules! debug_assert_ne {
 /// ```
 #[unstable(feature = "assert_matches", issue = "82775")]
 #[allow_internal_unstable(assert_matches)]
-#[rustc_macro_transparency = "semitransparent"]
+#[rustc_macro_transparency = "semiopaque"]
 pub macro debug_assert_matches($($arg:tt)*) {
     if $crate::cfg!(debug_assertions) {
         $crate::assert_matches::assert_matches!($($arg)*);

library/core/src/marker.rs

@@ -466,7 +466,7 @@ pub trait Copy: Clone {
 /// Derive macro generating an impl of the trait `Copy`.
 #[rustc_builtin_macro]
 #[stable(feature = "builtin_macro_prelude", since = "1.38.0")]
-#[allow_internal_unstable(core_intrinsics, derive_clone_copy)]
+#[allow_internal_unstable(core_intrinsics, derive_clone_copy_internals)]
 pub macro Copy($item:item) {
     /* compiler built-in */
 }