Rollup of 6 pull requests

src/bootstrap/channel.rs

@@ -13,7 +13,7 @@ use build_helper::output;
 use crate::Build;
 
 // The version number
-pub const CFG_RELEASE_NUM: &str = "1.39.0";
+pub const CFG_RELEASE_NUM: &str = "1.40.0";
 
 pub struct GitInfo {
     inner: Option<Info>,

src/liballoc/alloc.rs

@@ -240,7 +240,6 @@ pub(crate) unsafe fn box_free<T: ?Sized>(ptr: Unique<T>) {
 #[stable(feature = "global_alloc", since = "1.28.0")]
 #[rustc_allocator_nounwind]
 pub fn handle_alloc_error(layout: Layout) -> ! {
-    #[cfg_attr(bootstrap, allow(improper_ctypes))]
     extern "Rust" {
         #[lang = "oom"]
         fn oom_impl(layout: Layout) -> !;

src/liballoc/lib.rs

@@ -117,7 +117,6 @@
 #![feature(allocator_internals)]
 #![feature(on_unimplemented)]
 #![feature(rustc_const_unstable)]
-#![cfg_attr(bootstrap, feature(const_vec_new))]
 #![feature(slice_partition_dedup)]
 #![feature(maybe_uninit_extra, maybe_uninit_slice)]
 #![feature(alloc_layout_extra)]

src/liballoc/string.rs

@@ -369,7 +369,6 @@ impl String {
     /// ```
     #[inline]
     #[stable(feature = "rust1", since = "1.0.0")]
-    #[cfg_attr(bootstrap, rustc_const_unstable(feature = "const_string_new"))]
     pub const fn new() -> String {
         String { vec: Vec::new() }
     }

src/liballoc/vec.rs

@@ -291,7 +291,7 @@ use crate::raw_vec::RawVec;
 /// [`reserve`]: ../../std/vec/struct.Vec.html#method.reserve
 /// [owned slice]: ../../std/boxed/struct.Box.html
 #[stable(feature = "rust1", since = "1.0.0")]
-#[cfg_attr(all(not(bootstrap), not(test)), rustc_diagnostic_item = "vec_type")]
+#[cfg_attr(not(test), rustc_diagnostic_item = "vec_type")]
 pub struct Vec<T> {
     buf: RawVec<T>,
     len: usize,
@@ -314,7 +314,6 @@ impl<T> Vec<T> {
     /// ```
     #[inline]
     #[stable(feature = "rust1", since = "1.0.0")]
-    #[cfg_attr(bootstrap, rustc_const_unstable(feature = "const_vec_new"))]
     pub const fn new() -> Vec<T> {
         Vec {
             buf: RawVec::NEW,

src/libcore/bool.rs

@@ -1,6 +1,5 @@
 //! impl bool {}
 
-#[cfg(not(bootstrap))]
 #[lang = "bool"]
 impl bool {
     /// Returns `Some(t)` if the `bool` is `true`, or `None` otherwise.

src/libcore/clone.rs

@@ -135,7 +135,6 @@ pub trait Clone : Sized {
 
 /// Derive macro generating an impl of the trait `Clone`.
 #[rustc_builtin_macro]
-#[cfg_attr(bootstrap, rustc_macro_transparency = "semitransparent")]
 #[stable(feature = "builtin_macro_prelude", since = "1.38.0")]
 #[allow_internal_unstable(core_intrinsics, derive_clone_copy)]
 pub macro Clone($item:item) { /* compiler built-in */ }

src/libcore/cmp.rs

@@ -210,7 +210,6 @@ pub trait PartialEq<Rhs: ?Sized = Self> {
 
 /// Derive macro generating an impl of the trait `PartialEq`.
 #[rustc_builtin_macro]
-#[cfg_attr(bootstrap, rustc_macro_transparency = "semitransparent")]
 #[stable(feature = "builtin_macro_prelude", since = "1.38.0")]
 #[allow_internal_unstable(core_intrinsics)]
 pub macro PartialEq($item:item) { /* compiler built-in */ }
@@ -273,7 +272,6 @@ pub trait Eq: PartialEq<Self> {
 
 /// Derive macro generating an impl of the trait `Eq`.
 #[rustc_builtin_macro]
-#[cfg_attr(bootstrap, rustc_macro_transparency = "semitransparent")]
 #[stable(feature = "builtin_macro_prelude", since = "1.38.0")]
 #[allow_internal_unstable(core_intrinsics, derive_eq)]
 pub macro Eq($item:item) { /* compiler built-in */ }
@@ -624,7 +622,6 @@ pub trait Ord: Eq + PartialOrd<Self> {
 
 /// Derive macro generating an impl of the trait `Ord`.
 #[rustc_builtin_macro]
-#[cfg_attr(bootstrap, rustc_macro_transparency = "semitransparent")]
 #[stable(feature = "builtin_macro_prelude", since = "1.38.0")]
 #[allow_internal_unstable(core_intrinsics)]
 pub macro Ord($item:item) { /* compiler built-in */ }
@@ -873,7 +870,6 @@ pub trait PartialOrd<Rhs: ?Sized = Self>: PartialEq<Rhs> {
 
 /// Derive macro generating an impl of the trait `PartialOrd`.
 #[rustc_builtin_macro]
-#[cfg_attr(bootstrap, rustc_macro_transparency = "semitransparent")]
 #[stable(feature = "builtin_macro_prelude", since = "1.38.0")]
 #[allow_internal_unstable(core_intrinsics)]
 pub macro PartialOrd($item:item) { /* compiler built-in */ }

src/libcore/default.rs

@@ -117,7 +117,6 @@ pub trait Default: Sized {
 
 /// Derive macro generating an impl of the trait `Default`.
 #[rustc_builtin_macro]
-#[cfg_attr(bootstrap, rustc_macro_transparency = "semitransparent")]
 #[stable(feature = "builtin_macro_prelude", since = "1.38.0")]
 #[allow_internal_unstable(core_intrinsics)]
 pub macro Default($item:item) { /* compiler built-in */ }

src/libcore/fmt/mod.rs

@@ -518,8 +518,7 @@ impl Display for Arguments<'_> {
     label="`{Self}` cannot be formatted using `{{:?}}` because it doesn't implement `{Debug}`",
 )]
 #[doc(alias = "{:?}")]
-#[cfg_attr(bootstrap, lang = "debug_trait")]
-#[cfg_attr(not(bootstrap), rustc_diagnostic_item = "debug_trait")]
+#[rustc_diagnostic_item = "debug_trait"]
 pub trait Debug {
     /// Formats the value using the given formatter.
     ///
@@ -550,7 +549,6 @@ pub trait Debug {
 pub(crate) mod macros {
     /// Derive macro generating an impl of the trait `Debug`.
     #[rustc_builtin_macro]
-    #[cfg_attr(bootstrap, rustc_macro_transparency = "semitransparent")]
     #[stable(feature = "builtin_macro_prelude", since = "1.38.0")]
     #[allow_internal_unstable(core_intrinsics)]
     pub macro Debug($item:item) { /* compiler built-in */ }

src/libcore/hash/mod.rs

@@ -202,7 +202,6 @@ pub trait Hash {
 pub(crate) mod macros {
     /// Derive macro generating an impl of the trait `Hash`.
     #[rustc_builtin_macro]
-    #[cfg_attr(bootstrap, rustc_macro_transparency = "semitransparent")]
     #[stable(feature = "builtin_macro_prelude", since = "1.38.0")]
     #[allow_internal_unstable(core_intrinsics)]
     pub macro Hash($item:item) { /* compiler built-in */ }

src/libcore/intrinsics.rs

@@ -1299,38 +1299,16 @@ extern "rust-intrinsic" {
     /// The stabilized versions of this intrinsic are available on the integer
     /// primitives via the `wrapping_add` method. For example,
     /// [`std::u32::wrapping_add`](../../std/primitive.u32.html#method.wrapping_add)
-    #[cfg(bootstrap)]
-    pub fn overflowing_add<T>(a: T, b: T) -> T;
-    /// Returns (a - b) mod 2<sup>N</sup>, where N is the width of T in bits.
-    /// The stabilized versions of this intrinsic are available on the integer
-    /// primitives via the `wrapping_sub` method. For example,
-    /// [`std::u32::wrapping_sub`](../../std/primitive.u32.html#method.wrapping_sub)
-    #[cfg(bootstrap)]
-    pub fn overflowing_sub<T>(a: T, b: T) -> T;
-    /// Returns (a * b) mod 2<sup>N</sup>, where N is the width of T in bits.
-    /// The stabilized versions of this intrinsic are available on the integer
-    /// primitives via the `wrapping_mul` method. For example,
-    /// [`std::u32::wrapping_mul`](../../std/primitive.u32.html#method.wrapping_mul)
-    #[cfg(bootstrap)]
-    pub fn overflowing_mul<T>(a: T, b: T) -> T;
-
-    /// Returns (a + b) mod 2<sup>N</sup>, where N is the width of T in bits.
-    /// The stabilized versions of this intrinsic are available on the integer
-    /// primitives via the `wrapping_add` method. For example,
-    /// [`std::u32::wrapping_add`](../../std/primitive.u32.html#method.wrapping_add)
-    #[cfg(not(bootstrap))]
     pub fn wrapping_add<T>(a: T, b: T) -> T;
     /// Returns (a - b) mod 2<sup>N</sup>, where N is the width of T in bits.
     /// The stabilized versions of this intrinsic are available on the integer
     /// primitives via the `wrapping_sub` method. For example,
     /// [`std::u32::wrapping_sub`](../../std/primitive.u32.html#method.wrapping_sub)
-    #[cfg(not(bootstrap))]
     pub fn wrapping_sub<T>(a: T, b: T) -> T;
     /// Returns (a * b) mod 2<sup>N</sup>, where N is the width of T in bits.
     /// The stabilized versions of this intrinsic are available on the integer
     /// primitives via the `wrapping_mul` method. For example,
     /// [`std::u32::wrapping_mul`](../../std/primitive.u32.html#method.wrapping_mul)
-    #[cfg(not(bootstrap))]
     pub fn wrapping_mul<T>(a: T, b: T) -> T;
 
     /// Computes `a + b`, while saturating at numeric bounds.

src/libcore/lib.rs

@@ -87,7 +87,6 @@
 #![feature(link_llvm_intrinsics)]
 #![feature(never_type)]
 #![feature(nll)]
-#![cfg_attr(bootstrap, feature(bind_by_move_pattern_guards))]
 #![feature(exhaustive_patterns)]
 #![feature(no_core)]
 #![feature(on_unimplemented)]
@@ -120,9 +119,6 @@
 #![feature(rtm_target_feature)]
 #![feature(f16c_target_feature)]
 #![feature(hexagon_target_feature)]
-#![cfg_attr(bootstrap, feature(const_slice_len))]
-#![cfg_attr(bootstrap, feature(const_str_as_bytes))]
-#![cfg_attr(bootstrap, feature(const_str_len))]
 #![feature(const_int_conversion)]
 #![feature(const_transmute)]
 #![feature(non_exhaustive)]

src/libcore/macros.rs

@@ -1236,10 +1236,8 @@ pub(crate) mod builtin {
     pub macro test($item:item) { /* compiler built-in */ }
 
     /// Attribute macro applied to a function to turn it into a benchmark test.
-    #[cfg_attr(not(bootstrap), unstable(soft, feature = "test", issue = "50297",
-               reason = "`bench` is a part of custom test frameworks which are unstable"))]
-    #[cfg_attr(bootstrap, unstable(feature = "test", issue = "50297",
-               reason = "`bench` is a part of custom test frameworks which are unstable"))]
+    #[unstable(soft, feature = "test", issue = "50297",
+               reason = "`bench` is a part of custom test frameworks which are unstable")]
     #[allow_internal_unstable(test, rustc_attrs)]
     #[rustc_builtin_macro]
     pub macro bench($item:item) { /* compiler built-in */ }

src/libcore/marker.rs

@@ -290,7 +290,6 @@ pub trait Copy : Clone {
 
 /// Derive macro generating an impl of the trait `Copy`.
 #[rustc_builtin_macro]
-#[cfg_attr(bootstrap, rustc_macro_transparency = "semitransparent")]
 #[stable(feature = "builtin_macro_prelude", since = "1.38.0")]
 #[allow_internal_unstable(core_intrinsics, derive_clone_copy)]
 pub macro Copy($item:item) { /* compiler built-in */ }

src/libcore/num/mod.rs

@@ -1112,13 +1112,7 @@ $EndFeature, "
                           without modifying the original"]
             #[inline]
             pub const fn wrapping_add(self, rhs: Self) -> Self {
-                #[cfg(bootstrap)] {
-                    intrinsics::overflowing_add(self, rhs)
-                }
-
-                #[cfg(not(bootstrap))] {
-                    intrinsics::wrapping_add(self, rhs)
-                }
+                intrinsics::wrapping_add(self, rhs)
             }
         }
 
@@ -1141,13 +1135,7 @@ $EndFeature, "
                           without modifying the original"]
             #[inline]
             pub const fn wrapping_sub(self, rhs: Self) -> Self {
-                #[cfg(bootstrap)] {
-                    intrinsics::overflowing_sub(self, rhs)
-                }
-
-                #[cfg(not(bootstrap))] {
-                    intrinsics::wrapping_sub(self, rhs)
-                }
+                intrinsics::wrapping_sub(self, rhs)
             }
         }
 
@@ -1169,13 +1157,7 @@ $EndFeature, "
                           without modifying the original"]
             #[inline]
             pub const fn wrapping_mul(self, rhs: Self) -> Self {
-                #[cfg(bootstrap)] {
-                    intrinsics::overflowing_mul(self, rhs)
-                }
-
-                #[cfg(not(bootstrap))] {
-                    intrinsics::wrapping_mul(self, rhs)
-                }
+                intrinsics::wrapping_mul(self, rhs)
             }
         }
 
@@ -1402,7 +1384,16 @@ $EndFeature, "
             #[stable(feature = "no_panic_abs", since = "1.13.0")]
             #[inline]
             pub const fn wrapping_abs(self) -> Self {
-                (self ^ (self >> ($BITS - 1))).wrapping_sub(self >> ($BITS - 1))
+                // sign is -1 (all ones) for negative numbers, 0 otherwise.
+                let sign = self >> ($BITS - 1);
+                // For positive self, sign == 0 so the expression is simply
+                // (self ^ 0).wrapping_sub(0) == self == abs(self).
+                //
+                // For negative self, self ^ sign == self ^ all_ones.
+                // But all_ones ^ self == all_ones - self == -1 - self.
+                // So for negative numbers, (self ^ sign).wrapping_sub(sign) is
+                // (-1 - self).wrapping_sub(-1) == -self == abs(self).
+                (self ^ sign).wrapping_sub(sign)
             }
         }
 
@@ -1761,7 +1752,7 @@ $EndFeature, "
             #[stable(feature = "no_panic_abs", since = "1.13.0")]
             #[inline]
             pub const fn overflowing_abs(self) -> (Self, bool) {
-                (self ^ (self >> ($BITS - 1))).overflowing_sub(self >> ($BITS - 1))
+                (self.wrapping_abs(), self == Self::min_value())
             }
         }
 
@@ -1969,7 +1960,21 @@ $EndFeature, "
                 // Note that the #[inline] above means that the overflow
                 // semantics of the subtraction depend on the crate we're being
                 // inlined into.
-                (self ^ (self >> ($BITS - 1))) - (self >> ($BITS - 1))
+
+                // sign is -1 (all ones) for negative numbers, 0 otherwise.
+                let sign = self >> ($BITS - 1);
+                // For positive self, sign == 0 so the expression is simply
+                // (self ^ 0) - 0 == self == abs(self).
+                //
+                // For negative self, self ^ sign == self ^ all_ones.
+                // But all_ones ^ self == all_ones - self == -1 - self.
+                // So for negative numbers, (self ^ sign) - sign is
+                // (-1 - self) - -1 == -self == abs(self).
+                //
+                // The subtraction overflows when self is min_value(), because
+                // (-1 - min_value()) - -1 is max_value() - -1 which overflows.
+                // This is exactly when we want self.abs() to overflow.
+                (self ^ sign) - sign
             }
         }
 
@@ -3040,13 +3045,7 @@ $EndFeature, "
                           without modifying the original"]
             #[inline]
             pub const fn wrapping_add(self, rhs: Self) -> Self {
-                #[cfg(bootstrap)] {
-                    intrinsics::overflowing_add(self, rhs)
-                }
-
-                #[cfg(not(bootstrap))] {
-                    intrinsics::wrapping_add(self, rhs)
-                }
+                intrinsics::wrapping_add(self, rhs)
             }
         }
 
@@ -3068,13 +3067,7 @@ $EndFeature, "
                           without modifying the original"]
             #[inline]
             pub const fn wrapping_sub(self, rhs: Self) -> Self {
-                #[cfg(bootstrap)] {
-                    intrinsics::overflowing_sub(self, rhs)
-                }
-
-                #[cfg(not(bootstrap))] {
-                    intrinsics::wrapping_sub(self, rhs)
-                }
+                intrinsics::wrapping_sub(self, rhs)
             }
         }
 
@@ -3097,13 +3090,7 @@ $EndFeature, "
                           without modifying the original"]
         #[inline]
         pub const fn wrapping_mul(self, rhs: Self) -> Self {
-            #[cfg(bootstrap)] {
-                intrinsics::overflowing_mul(self, rhs)
-            }
-
-            #[cfg(not(bootstrap))] {
-                intrinsics::wrapping_mul(self, rhs)
-            }
+            intrinsics::wrapping_mul(self, rhs)
         }
 
         doc_comment! {

src/libcore/panicking.rs

@@ -71,7 +71,6 @@ pub fn panic_fmt(fmt: fmt::Arguments<'_>, file_line_col: &(&'static str, u32, u3
     }
 
     // NOTE This function never crosses the FFI boundary; it's a Rust-to-Rust call
-    #[cfg_attr(bootstrap, allow(improper_ctypes))]
     extern "Rust" {
         #[lang = "panic_impl"]
         fn panic_impl(pi: &PanicInfo<'_>) -> !;

src/libcore/slice/mod.rs

@@ -62,9 +62,8 @@ impl<T> [T] {
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
     #[inline]
-    #[cfg_attr(bootstrap, rustc_const_unstable(feature = "const_slice_len"))]
     // SAFETY: const sound because we transmute out the length field as a usize (which it must be)
-    #[cfg_attr(not(bootstrap), allow_internal_unstable(const_fn_union))]
+    #[allow_internal_unstable(const_fn_union)]
     pub const fn len(&self) -> usize {
         unsafe {
             crate::ptr::Repr { rust: self }.raw.len
@@ -81,7 +80,6 @@ impl<T> [T] {
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
     #[inline]
-    #[cfg_attr(bootstrap, rustc_const_unstable(feature = "const_slice_len"))]
     pub const fn is_empty(&self) -> bool {
         self.len() == 0
     }