Auto merge of #55859 - pietroalbini:rollup, r=kennytm

Rollup of 17 pull requests

Successful merges:

 - #55630 (resolve: Filter away macro prelude in modules with `#[no_implicit_prelude]` on 2018 edition)
 - #55687 (Take supertraits into account when calculating associated types)
 - #55745 (Convert `outlives_components`' return value to a `SmallVec` outparam.)
 - #55764 (Fix Rc/Arc allocation layout)
 - #55792 (Prevent ICE in const-prop array oob check)
 - #55799 (Removed unneeded instance of `// revisions` from a lint test)
 - #55800 (Fix ICE in `return_type_impl_trait`)
 - #55801 (NLL: Update box insensitivity test)
 - #55802 (Don't inline virtual calls (take 2))
 - #55816 (Use `SmallVec` to avoid allocations in `from_decimal_string`.)
 - #55819 (Typecheck patterns of all match arms first, so we get types for bindings)
 - #55822 (ICE with #![feature(nll)] and elided lifetimes)
 - #55828 (Add missing `rustc_promotable` attribute to unsigned `min_value` and `max_value`)
 - #55839 (Fix docstring spelling mistakes)
 - #55844 (Fix documentation typos.)
 - #55845 (Set BINARYEN_TRAP_MODE=clamp)
 - #55856 (rustdoc: refactor: move all static-file include!s into a single module)

Author: bors

src/Cargo.lock

@@ -2096,6 +2096,7 @@ version = "0.0.0"
 dependencies = [
  "bitflags 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc_cratesio_shim 0.0.0",
+ "smallvec 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]

src/liballoc/rc.rs

@@ -672,14 +672,16 @@ impl<T: ?Sized> Rc<T> {
         // Previously, layout was calculated on the expression
         // `&*(ptr as *const RcBox<T>)`, but this created a misaligned
         // reference (see #54908).
-        let (layout, _) = Layout::new::<RcBox<()>>()
-            .extend(Layout::for_value(&*ptr)).unwrap();
+        let layout = Layout::new::<RcBox<()>>()
+            .extend(Layout::for_value(&*ptr)).unwrap().0
+            .pad_to_align().unwrap();
 
         let mem = Global.alloc(layout)
             .unwrap_or_else(|_| handle_alloc_error(layout));
 
         // Initialize the RcBox
         let inner = set_data_ptr(ptr as *mut T, mem.as_ptr() as *mut u8) as *mut RcBox<T>;
+        debug_assert_eq!(Layout::for_value(&*inner), layout);
 
         ptr::write(&mut (*inner).strong, Cell::new(1));
         ptr::write(&mut (*inner).weak, Cell::new(1));

src/liballoc/sync.rs

@@ -575,14 +575,16 @@ impl<T: ?Sized> Arc<T> {
         // Previously, layout was calculated on the expression
         // `&*(ptr as *const ArcInner<T>)`, but this created a misaligned
         // reference (see #54908).
-        let (layout, _) = Layout::new::<ArcInner<()>>()
-            .extend(Layout::for_value(&*ptr)).unwrap();
+        let layout = Layout::new::<ArcInner<()>>()
+            .extend(Layout::for_value(&*ptr)).unwrap().0
+            .pad_to_align().unwrap();
 
         let mem = Global.alloc(layout)
             .unwrap_or_else(|_| handle_alloc_error(layout));
 
         // Initialize the ArcInner
         let inner = set_data_ptr(ptr as *mut T, mem.as_ptr() as *mut u8) as *mut ArcInner<T>;
+        debug_assert_eq!(Layout::for_value(&*inner), layout);
 
         ptr::write(&mut (*inner).strong, atomic::AtomicUsize::new(1));
         ptr::write(&mut (*inner).weak, atomic::AtomicUsize::new(1));

src/libcore/alloc.rs

@@ -218,6 +218,23 @@ impl Layout {
         len_rounded_up.wrapping_sub(len)
     }
 
+    /// Creates a layout by rounding the size of this layout up to a multiple
+    /// of the layout's alignment.
+    ///
+    /// Returns `Err` if the padded size would overflow.
+    ///
+    /// This is equivalent to adding the result of `padding_needed_for`
+    /// to the layout's current size.
+    #[unstable(feature = "alloc_layout_extra", issue = "55724")]
+    #[inline]
+    pub fn pad_to_align(&self) -> Result<Layout, LayoutErr> {
+        let pad = self.padding_needed_for(self.align());
+        let new_size = self.size().checked_add(pad)
+            .ok_or(LayoutErr { private: () })?;
+
+        Layout::from_size_align(new_size, self.align())
+    }
+
     /// Creates a layout describing the record for `n` instances of
     /// `self`, with a suitable amount of padding between each to
     /// ensure that each instance is given its requested size and
@@ -506,7 +523,7 @@ pub unsafe trait GlobalAlloc {
         ptr
     }
 
-    /// Shink or grow a block of memory to the given `new_size`.
+    /// Shrink or grow a block of memory to the given `new_size`.
     /// The block is described by the given `ptr` pointer and `layout`.
     ///
     /// If this returns a non-null pointer, then ownership of the memory block
@@ -757,7 +774,7 @@ pub unsafe trait Alloc {
     // realloc. alloc_excess, realloc_excess
 
     /// Returns a pointer suitable for holding data described by
-    /// a new layout with `layout`’s alginment and a size given
+    /// a new layout with `layout`’s alignment and a size given
     /// by `new_size`. To
     /// accomplish this, this may extend or shrink the allocation
     /// referenced by `ptr` to fit the new layout.

src/libcore/future/future.rs

@@ -17,7 +17,7 @@ use ops;
 use pin::Pin;
 use task::{Poll, LocalWaker};
 
-/// A future represents an asychronous computation.
+/// A future represents an asynchronous computation.
 ///
 /// A future is a value that may not have finished computing yet. This kind of
 /// "asynchronous value" makes it possible for a thread to continue doing useful

src/libcore/lib.rs

@@ -228,7 +228,7 @@ mod nonzero;
 mod tuple;
 mod unit;
 
-// Pull in the the `coresimd` crate directly into libcore. This is where all the
+// Pull in the `coresimd` crate directly into libcore. This is where all the
 // architecture-specific (and vendor-specific) intrinsics are defined. AKA
 // things like SIMD and such. Note that the actual source for all this lies in a
 // different repository, rust-lang-nursery/stdsimd. That's why the setup here is

src/libcore/macros.rs

@@ -350,9 +350,8 @@ macro_rules! try {
 /// assert_eq!(v, b"s = \"abc 123\"");
 /// ```
 ///
-/// Note: This macro can be used in `no_std` setups as well
-/// In a `no_std` setup you are responsible for the
-/// implementation details of the components.
+/// Note: This macro can be used in `no_std` setups as well.
+/// In a `no_std` setup you are responsible for the implementation details of the components.
 ///
 /// ```no_run
 /// # extern crate core;
@@ -440,7 +439,7 @@ macro_rules! writeln {
 ///
 /// If the determination that the code is unreachable proves incorrect, the
 /// program immediately terminates with a [`panic!`].  The function [`unreachable_unchecked`],
-/// which belongs to the [`std::hint`] module, informs the compilier to
+/// which belongs to the [`std::hint`] module, informs the compiler to
 /// optimize the code out of the release version entirely.
 ///
 /// [`panic!`]:  ../std/macro.panic.html

src/libcore/mem.rs

@@ -202,7 +202,7 @@ pub fn forget<T>(t: T) {
 ///
 /// ## Size of Enums
 ///
-/// Enums that carry no data other than the descriminant have the same size as C enums
+/// Enums that carry no data other than the discriminant have the same size as C enums
 /// on the platform they are compiled for.
 ///
 /// ## Size of Unions
@@ -1081,7 +1081,7 @@ impl<T> MaybeUninit<T> {
     ///
     /// # Unsafety
     ///
-    /// It is up to the caller to guarantee that the the `MaybeUninit` really is in an initialized
+    /// It is up to the caller to guarantee that the `MaybeUninit` really is in an initialized
     /// state, otherwise this will immediately cause undefined behavior.
     #[unstable(feature = "maybe_uninit", issue = "53491")]
     pub unsafe fn into_inner(self) -> T {
@@ -1092,7 +1092,7 @@ impl<T> MaybeUninit<T> {
     ///
     /// # Unsafety
     ///
-    /// It is up to the caller to guarantee that the the `MaybeUninit` really is in an initialized
+    /// It is up to the caller to guarantee that the `MaybeUninit` really is in an initialized
     /// state, otherwise this will immediately cause undefined behavior.
     #[unstable(feature = "maybe_uninit", issue = "53491")]
     pub unsafe fn get_ref(&self) -> &T {
@@ -1103,7 +1103,7 @@ impl<T> MaybeUninit<T> {
     ///
     /// # Unsafety
     ///
-    /// It is up to the caller to guarantee that the the `MaybeUninit` really is in an initialized
+    /// It is up to the caller to guarantee that the `MaybeUninit` really is in an initialized
     /// state, otherwise this will immediately cause undefined behavior.
     #[unstable(feature = "maybe_uninit", issue = "53491")]
     pub unsafe fn get_mut(&mut self) -> &mut T {

src/libcore/num/mod.rs

@@ -2152,6 +2152,7 @@ Basic usage:
 ", $Feature, "assert_eq!(", stringify!($SelfT), "::min_value(), 0);", $EndFeature, "
 ```"),
             #[stable(feature = "rust1", since = "1.0.0")]
+            #[rustc_promotable]
             #[inline]
             pub const fn min_value() -> Self { 0 }
         }
@@ -2168,6 +2169,7 @@ Basic usage:
 stringify!($MaxV), ");", $EndFeature, "
 ```"),
             #[stable(feature = "rust1", since = "1.0.0")]
+            #[rustc_promotable]
             #[inline]
             pub const fn max_value() -> Self { !0 }
         }

src/libcore/pin.rs

@@ -3,7 +3,7 @@
 //! It is sometimes useful to have objects that are guaranteed to not move,
 //! in the sense that their placement in memory does not change, and can thus be relied upon.
 //!
-//! A prime example of such a scenario would be building self-referencial structs,
+//! A prime example of such a scenario would be building self-referential structs,
 //! since moving an object with pointers to itself will invalidate them,
 //! which could cause undefined behavior.
 //!
@@ -39,7 +39,7 @@
 //! use std::marker::Pinned;
 //! use std::ptr::NonNull;
 //!
-//! // This is a self referencial struct since the slice field points to the data field.
+//! // This is a self-referential struct since the slice field points to the data field.
 //! // We cannot inform the compiler about that with a normal reference,
 //! // since this pattern cannot be described with the usual borrowing rules.
 //! // Instead we use a raw pointer, though one which is known to not be null,