Auto merge of #44033 - GuillaumeGomez:rollup, r=GuillaumeGomez

Rollup of 5 pull requests

- Successful merges: #43993, #44001, #44010, #44014, #44029
- Failed merges:

Author: bors

RELEASES.md

@@ -92,7 +92,7 @@ Stabilized APIs
 Cargo
 -----
 - [Cargo API token location moved from `~/.cargo/config` to
-  `~/cargo/credentials`.][cargo/3978]
+  `~/.cargo/credentials`.][cargo/3978]
 - [Cargo will now build `main.rs` binaries that are in sub-directories of
   `src/bin`.][cargo/4214] ie. Having `src/bin/server/main.rs` and
   `src/bin/client/main.rs` generates `target/debug/server` and `target/debug/client`
@@ -172,7 +172,6 @@ Compatibility Notes
 [`slice::sort_unstable`]: https://doc.rust-lang.org/std/primitive.slice.html#method.sort_unstable
 [`ste::from_boxed_utf8_unchecked`]: https://doc.rust-lang.org/std/str/fn.from_boxed_utf8_unchecked.html
 [`str::as_bytes_mut`]: https://doc.rust-lang.org/std/primitive.str.html#method.as_bytes_mut
-[`str::as_bytes_mut`]: https://doc.rust-lang.org/std/primitive.str.html#method.as_bytes_mut
 [`str::from_utf8_mut`]: https://doc.rust-lang.org/std/str/fn.from_utf8_mut.html
 [`str::from_utf8_unchecked_mut`]: https://doc.rust-lang.org/std/str/fn.from_utf8_unchecked_mut.html
 [`str::get_mut`]: https://doc.rust-lang.org/std/primitive.str.html#method.get_mut
@@ -898,6 +897,9 @@ Compatibility Notes
 * [Ctrl-Z returns from `Stdin.read()` when reading from the console on
   Windows][38274]
 * [Clean up semantics of `self` in an import list][38313]
+* Reimplemented lifetime elision. This change was almost entirely compatible
+  with existing code, but it did close a number of small bugs and loopholes,
+  as well as being more accepting in some other [cases][41105].
 
 [37057]: https://github.com/rust-lang/rust/pull/37057
 [37761]: https://github.com/rust-lang/rust/pull/37761
@@ -932,6 +934,7 @@ Compatibility Notes
 [39048]: https://github.com/rust-lang/rust/pull/39048
 [39282]: https://github.com/rust-lang/rust/pull/39282
 [39379]: https://github.com/rust-lang/rust/pull/39379
+[41105]: https://github.com/rust-lang/rust/issues/41105
 [`<*const T>::wrapping_offset`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.wrapping_offset
 [`<*mut T>::wrapping_offset`]: https://doc.rust-lang.org/std/primitive.pointer.html#method.wrapping_offset
 [`Duration::checked_add`]: https://doc.rust-lang.org/std/time/struct.Duration.html#method.checked_add

src/bootstrap/README.md

@@ -73,16 +73,19 @@ The script accepts commands, flags, and arguments to determine what to do:
 
 ## Configuring rustbuild
 
-There are currently two primary methods for configuring the rustbuild build
-system. First, the `./configure` options serialized in `config.mk` will be
-parsed and read. That is, if any `./configure` options are passed, they'll be
-handled naturally.
+There are currently two methods for configuring the rustbuild build system.
 
-Next, rustbuild offers a TOML-based configuration system with a `config.toml`
+First, rustbuild offers a TOML-based configuration system with a `config.toml`
 file in the same location as `config.mk`. An example of this configuration can
-be found at `config.toml.example`, and the configuration file
-can also be passed as `--config path/to/config.toml` if the build system is
-being invoked manually (via the python script).
+be found at `config.toml.example`, and the configuration file can also be passed
+as `--config path/to/config.toml` if the build system is being invoked manually
+(via the python script).
+
+Next, the `./configure` options serialized in `config.mk` will be
+parsed and read. That is, if any `./configure` options are passed, they'll be
+handled naturally. `./configure` should almost never be used for local
+installations, and is primarily useful for CI. Prefer to customize behavior
+using `config.toml`.
 
 Finally, rustbuild makes use of the [gcc-rs crate] which has [its own
 method][env-vars] of configuring C compilers and C flags via environment
@@ -310,17 +313,18 @@ After that, each module in rustbuild should have enough documentation to keep
 you up and running. Some general areas that you may be interested in modifying
 are:
 
-* Adding a new build tool? Take a look at `bootstrap/step.rs` for examples of
+* Adding a new build tool? Take a look at `bootstrap/tool.rs` for examples of
   other tools.
 * Adding a new compiler crate? Look no further! Adding crates can be done by
   adding a new directory with `Cargo.toml` followed by configuring all
   `Cargo.toml` files accordingly.
-* Adding a new dependency from crates.io? We're still working on that, so hold
-  off on that for now.
-* Adding a new configuration option? Take a look at `bootstrap/config.rs` or
-  perhaps `bootstrap/flags.rs` and then modify the build elsewhere to read that
-  option.
+* Adding a new dependency from crates.io? This should just work inside the
+  compiler artifacts stage (everything other than libtest and libstd).
+* Adding a new configuration option? You'll want to modify `bootstrap/flags.rs`
+  for command line flags and then `bootstrap/config.rs` to copy the flags to the
+  `Config` struct.
 * Adding a sanity check? Take a look at `bootstrap/sanity.rs`.
 
-If you have any questions feel free to reach out on `#rust-internals` on IRC or
-open an issue in the bug tracker!
+If you have any questions feel free to reach out on `#rust-infra` on IRC or ask on
+internals.rust-lang.org. When you encounter bugs, please file issues on the
+rust-lang/rust issue tracker.

src/librustc_borrowck/borrowck/gather_loans/move_error.rs

@@ -153,20 +153,19 @@ fn report_cannot_move_out_of<'a, 'tcx>(bccx: &BorrowckCtxt<'a, 'tcx>,
         }
 
         Categorization::Interior(ref b, mc::InteriorElement(ik)) => {
-            match (&b.ty.sty, ik) {
-                (&ty::TySlice(..), _) |
-                (_, Kind::Index) => {
-                    let mut err = struct_span_err!(bccx, move_from.span, E0508,
-                                                   "cannot move out of type `{}`, \
-                                                    a non-copy array",
-                                                   b.ty);
-                    err.span_label(move_from.span, "cannot move out of here");
-                    err
-                }
-                (_, Kind::Pattern) => {
+            let type_name = match (&b.ty.sty, ik) {
+                (&ty::TyArray(_, _), Kind::Index) => "array",
+                (&ty::TySlice(_), _) => "slice",
+                _ => {
                     span_bug!(move_from.span, "this path should not cause illegal move");
-                }
-            }
+                },
+            };
+            let mut err = struct_span_err!(bccx, move_from.span, E0508,
+                                           "cannot move out of type `{}`, \
+                                            a non-copy {}",
+                                           b.ty, type_name);
+            err.span_label(move_from.span, "cannot move out of here");
+            err
         }
 
         Categorization::Downcast(ref b, _) |

src/libstd/io/mod.rs

@@ -401,28 +401,29 @@ fn read_to_end<R: Read + ?Sized>(r: &mut R, buf: &mut Vec<u8>) -> Result<usize>
 ///
 /// Implementors of the `Read` trait are called 'readers'.
 ///
-/// Readers are defined by one required method, `read()`. Each call to `read`
+/// Readers are defined by one required method, [`read()`]. Each call to [`read()`]
 /// will attempt to pull bytes from this source into a provided buffer. A
-/// number of other methods are implemented in terms of `read()`, giving
+/// number of other methods are implemented in terms of [`read()`], giving
 /// implementors a number of ways to read bytes while only needing to implement
 /// a single method.
 ///
 /// Readers are intended to be composable with one another. Many implementors
-/// throughout `std::io` take and provide types which implement the `Read`
+/// throughout [`std::io`] take and provide types which implement the `Read`
 /// trait.
 ///
-/// Please note that each call to `read` may involve a system call, and
-/// therefore, using something that implements [`BufRead`][bufread], such as
-/// [`BufReader`][bufreader], will be more efficient.
-///
-/// [bufread]: trait.BufRead.html
-/// [bufreader]: struct.BufReader.html
+/// Please note that each call to [`read()`] may involve a system call, and
+/// therefore, using something that implements [`BufRead`], such as
+/// [`BufReader`], will be more efficient.
 ///
 /// # Examples
 ///
-/// [`File`][file]s implement `Read`:
+/// [`File`]s implement `Read`:
 ///
-/// [file]: ../fs/struct.File.html
+/// [`read()`]: trait.Read.html#tymethod.read
+/// [`std::io`]: ../../std/io/index.html
+/// [`File`]: ../fs/struct.File.html
+/// [`BufRead`]: trait.BufRead.html
+/// [`BufReader`]: struct.BufReader.html
 ///
 /// ```
 /// use std::io;
@@ -455,9 +456,9 @@ pub trait Read {
     ///
     /// This function does not provide any guarantees about whether it blocks
     /// waiting for data, but if an object needs to block for a read but cannot
-    /// it will typically signal this via an `Err` return value.
+    /// it will typically signal this via an [`Err`] return value.
     ///
-    /// If the return value of this method is `Ok(n)`, then it must be
+    /// If the return value of this method is [`Ok(n)`], then it must be
     /// guaranteed that `0 <= n <= buf.len()`. A nonzero `n` value indicates
     /// that the buffer `buf` has been filled in with `n` bytes of data from this
     /// source. If `n` is `0`, then it can indicate one of two scenarios:
@@ -478,14 +479,17 @@ pub trait Read {
     /// variant will be returned. If an error is returned then it must be
     /// guaranteed that no bytes were read.
     ///
-    /// An error of the `ErrorKind::Interrupted` kind is non-fatal and the read
+    /// An error of the [`ErrorKind::Interrupted`] kind is non-fatal and the read
     /// operation should be retried if there is nothing else to do.
     ///
     /// # Examples
     ///
-    /// [`File`][file]s implement `Read`:
+    /// [`File`]s implement `Read`:
     ///
-    /// [file]: ../fs/struct.File.html
+    /// [`Err`]: ../../std/result/enum.Result.html#variant.Err
+    /// [`Ok(n)`]: ../../std/result/enum.Result.html#variant.Ok
+    /// [`ErrorKind::Interrupted`]: ../../std/io/enum.ErrorKind.html#variant.Interrupted
+    /// [`File`]: ../fs/struct.File.html
     ///
     /// ```
     /// use std::io;
@@ -511,8 +515,8 @@ pub trait Read {
     /// buffers.
     ///
     /// If a `Read`er guarantees that it can work properly with uninitialized
-    /// memory, it should call `Initializer::nop()`. See the documentation for
-    /// `Initializer` for details.
+    /// memory, it should call [`Initializer::nop()`]. See the documentation for
+    /// [`Initializer`] for details.
     ///
     /// The behavior of this method must be independent of the state of the
     /// `Read`er - the method only takes `&self` so that it can be used through
@@ -523,6 +527,9 @@ pub trait Read {
     /// This method is unsafe because a `Read`er could otherwise return a
     /// non-zeroing `Initializer` from another `Read` type without an `unsafe`
     /// block.
+    ///
+    /// [`Initializer::nop()`]: ../../std/io/struct.Initializer.html#method.nop
+    /// [`Initializer`]: ../../std/io/struct.Initializer.html
     #[unstable(feature = "read_initializer", issue = "42788")]
     #[inline]
     unsafe fn initializer(&self) -> Initializer {
@@ -532,16 +539,16 @@ pub trait Read {
     /// Read all bytes until EOF in this source, placing them into `buf`.
     ///
     /// All bytes read from this source will be appended to the specified buffer
-    /// `buf`. This function will continuously call `read` to append more data to
-    /// `buf` until `read` returns either `Ok(0)` or an error of
-    /// non-`ErrorKind::Interrupted` kind.
+    /// `buf`. This function will continuously call [`read()`] to append more data to
+    /// `buf` until [`read()`] returns either [`Ok(0)`] or an error of
+    /// non-[`ErrorKind::Interrupted`] kind.
     ///
     /// If successful, this function will return the total number of bytes read.
     ///
     /// # Errors
     ///
     /// If this function encounters an error of the kind
-    /// `ErrorKind::Interrupted` then the error is ignored and the operation
+    /// [`ErrorKind::Interrupted`] then the error is ignored and the operation
     /// will continue.
     ///
     /// If any other read error is encountered then this function immediately
@@ -550,9 +557,12 @@ pub trait Read {
     ///
     /// # Examples
     ///
-    /// [`File`][file]s implement `Read`:
+    /// [`File`]s implement `Read`:
     ///
-    /// [file]: ../fs/struct.File.html
+    /// [`read()`]: trait.Read.html#tymethod.read
+    /// [`Ok(0)`]: ../../std/result/enum.Result.html#variant.Ok
+    /// [`ErrorKind::Interrupted`]: ../../std/io/enum.ErrorKind.html#variant.Interrupted
+    /// [`File`]: ../fs/struct.File.html
     ///
     /// ```
     /// use std::io;
@@ -633,11 +643,11 @@ pub trait Read {
     /// # Errors
     ///
     /// If this function encounters an error of the kind
-    /// `ErrorKind::Interrupted` then the error is ignored and the operation
+    /// [`ErrorKind::Interrupted`] then the error is ignored and the operation
     /// will continue.
     ///
     /// If this function encounters an "end of file" before completely filling
-    /// the buffer, it returns an error of the kind `ErrorKind::UnexpectedEof`.
+    /// the buffer, it returns an error of the kind [`ErrorKind::UnexpectedEof`].
     /// The contents of `buf` are unspecified in this case.
     ///
     /// If any other read error is encountered then this function immediately
@@ -649,9 +659,11 @@ pub trait Read {
     ///
     /// # Examples
     ///
-    /// [`File`][file]s implement `Read`:
+    /// [`File`]s implement `Read`:
     ///
-    /// [file]: ../fs/struct.File.html
+    /// [`File`]: ../fs/struct.File.html
+    /// [`ErrorKind::Interrupted`]: ../../std/io/enum.ErrorKind.html#variant.Interrupted
+    /// [`ErrorKind::UnexpectedEof`]: ../../std/io/enum.ErrorKind.html#variant.UnexpectedEof
     ///
     /// ```
     /// use std::io;
@@ -722,18 +734,24 @@ pub trait Read {
     #[stable(feature = "rust1", since = "1.0.0")]
     fn by_ref(&mut self) -> &mut Self where Self: Sized { self }
 
-    /// Transforms this `Read` instance to an `Iterator` over its bytes.
+    /// Transforms this `Read` instance to an [`Iterator`] over its bytes.
     ///
-    /// The returned type implements `Iterator` where the `Item` is `Result<u8,
-    /// R::Err>`.  The yielded item is `Ok` if a byte was successfully read and
-    /// `Err` otherwise for I/O errors. EOF is mapped to returning `None` from
+    /// The returned type implements [`Iterator`] where the `Item` is [`Result`]`<`[`u8`]`,
+    /// R::Err>`. The yielded item is [`Ok`] if a byte was successfully read and
+    /// [`Err`] otherwise for I/O errors. EOF is mapped to returning [`None`] from
     /// this iterator.
     ///
     /// # Examples
     ///
     /// [`File`][file]s implement `Read`:
     ///
     /// [file]: ../fs/struct.File.html
+    /// [`Iterator`]: ../../std/iter/trait.Iterator.html
+    /// [`Result`]: ../../std/result/enum.Result.html
+    /// [`u8`]: ../../std/primitive.u8.html
+    /// [`Ok`]: ../../std/result/enum.Result.html#variant.Ok
+    /// [`Err`]: ../../std/result/enum.Result.html#variant.Err
+    /// [`None`]: ../../std/option/enum.Option.html#variant.None
     ///
     /// ```
     /// use std::io;
@@ -754,22 +772,26 @@ pub trait Read {
         Bytes { inner: self }
     }
 
-    /// Transforms this `Read` instance to an `Iterator` over `char`s.
+    /// Transforms this `Read` instance to an [`Iterator`] over [`char`]s.
     ///
     /// This adaptor will attempt to interpret this reader as a UTF-8 encoded
-    /// sequence of characters. The returned iterator will return `None` once
+    /// sequence of characters. The returned iterator will return [`None`] once
     /// EOF is reached for this reader. Otherwise each element yielded will be a
-    /// `Result<char, E>` where `E` may contain information about what I/O error
+    /// [`Result`]`<`[`char`]`, E>` where `E` may contain information about what I/O error
     /// occurred or where decoding failed.
     ///
     /// Currently this adaptor will discard intermediate data read, and should
     /// be avoided if this is not desired.
     ///
     /// # Examples
     ///
-    /// [`File`][file]s implement `Read`:
+    /// [`File`]s implement `Read`:
     ///
-    /// [file]: ../fs/struct.File.html
+    /// [`File`]: ../fs/struct.File.html
+    /// [`Iterator`]: ../../std/iter/trait.Iterator.html
+    /// [`Result`]: ../../std/result/enum.Result.html
+    /// [`char`]: ../../std/primitive.char.html
+    /// [`None`]: ../../std/option/enum.Option.html#variant.None
     ///
     /// ```
     /// #![feature(io)]
@@ -832,15 +854,17 @@ pub trait Read {
     /// Creates an adaptor which will read at most `limit` bytes from it.
     ///
     /// This function returns a new instance of `Read` which will read at most
-    /// `limit` bytes, after which it will always return EOF (`Ok(0)`). Any
+    /// `limit` bytes, after which it will always return EOF ([`Ok(0)`]). Any
     /// read errors will not count towards the number of bytes read and future
-    /// calls to `read` may succeed.
+    /// calls to [`read()`] may succeed.
     ///
     /// # Examples
     ///
-    /// [`File`][file]s implement `Read`:
+    /// [`File`]s implement `Read`:
     ///
-    /// [file]: ../fs/struct.File.html
+    /// [`File`]: ../fs/struct.File.html
+    /// [`Ok(0)`]: ../../std/result/enum.Result.html#variant.Ok
+    /// [`read()`]: trait.Read.html#tymethod.read
     ///
     /// ```
     /// use std::io;

src/test/compile-fail/issue-12567.rs

@@ -15,12 +15,12 @@ fn match_vecs<'a, T>(l1: &'a [T], l2: &'a [T]) {
         (&[], &[]) => println!("both empty"),
         (&[], &[hd, ..]) | (&[hd, ..], &[])
             => println!("one empty"),
-        //~^^ ERROR: cannot move out of type `[T]`, a non-copy array
-        //~^^^ ERROR: cannot move out of type `[T]`, a non-copy array
+        //~^^ ERROR: cannot move out of type `[T]`, a non-copy slice
+        //~^^^ ERROR: cannot move out of type `[T]`, a non-copy slice
         (&[hd1, ..], &[hd2, ..])
             => println!("both nonempty"),
-        //~^^ ERROR: cannot move out of type `[T]`, a non-copy array
-        //~^^^ ERROR: cannot move out of type `[T]`, a non-copy array
+        //~^^ ERROR: cannot move out of type `[T]`, a non-copy slice
+        //~^^^ ERROR: cannot move out of type `[T]`, a non-copy slice
     }
 }
 

src/test/compile-fail/move-out-of-array-1.rs

@@ -24,5 +24,5 @@ fn main() {
 }
 
 fn foo(a: [D; 4], i: usize) -> D {
-    a[i] //~ ERROR cannot move out of type `[D; 4]`
+    a[i] //~ ERROR cannot move out of type `[D; 4]`, a non-copy array
 }

src/test/compile-fail/move-out-of-slice-1.rs

@@ -15,7 +15,7 @@ struct A;
 fn main() {
     let a: Box<[A]> = Box::new([A]);
     match a {
-        box [a] => {}, //~ ERROR cannot move out of type `[A]`
+        box [a] => {}, //~ ERROR cannot move out of type `[A]`, a non-copy slice
         _ => {}
     }
 }