Auto merge of #67080 - JohnTitor:rollup-2t6fm3u, r=JohnTitor

Rollup of 10 pull requests

Successful merges:

 - #66649 (VxWorks: fix issues in accessing environment variables)
 - #66764 (Tweak wording of `collect()` on bad target type)
 - #66900 (Clean up error codes)
 - #66974 ([CI] fix the `! isCI` check in src/ci/run.sh)
 - #66979 (Add long error for E0631 and update ui tests.)
 - #67017 (cleanup long error explanations)
 - #67021 (Fix docs for formatting delegations)
 - #67041 (add ExitStatusExt into prelude)
 - #67065 (Fix fetching arguments on the wasm32-wasi target)
 - #67066 (Update the revision of wasi-libc used in wasm32-wasi)

Failed merges:

r? @ghost

Author: bors

src/ci/docker/dist-various-2/build-wasi-toolchain.sh

@@ -12,7 +12,7 @@ export PATH=`pwd`/clang+llvm-9.0.0-x86_64-linux-gnu-ubuntu-14.04/bin:$PATH
 git clone https://github.com/CraneStation/wasi-libc
 
 cd wasi-libc
-git reset --hard a94d2d04e7722b323573da2bd04e909a5763d35b
+git reset --hard f645f498dfbbbc00a7a97874d33082d3605c3f21
 make -j$(nproc) INSTALL_DIR=/wasm32-wasi install
 
 cd ..

src/ci/run.sh

@@ -23,7 +23,7 @@ fi
 ci_dir=`cd $(dirname $0) && pwd`
 source "$ci_dir/shared.sh"
 
-if [ ! isCI ] || isCiBranch auto || isCiBranch beta; then
+if ! isCI || isCiBranch auto || isCiBranch beta; then
     RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --set build.print-step-timings --enable-verbose-tests"
 fi
 

src/libcore/fmt/mod.rs

@@ -662,7 +662,7 @@ pub trait Display {
 ///     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
 ///         let val = self.0;
 ///
-///         write!(f, "{:o}", val) // delegate to i32's implementation
+///         fmt::Octal::fmt(&val, f) // delegate to i32's implementation
 ///     }
 /// }
 ///
@@ -712,7 +712,7 @@ pub trait Octal {
 ///     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
 ///         let val = self.0;
 ///
-///         write!(f, "{:b}", val) // delegate to i32's implementation
+///         fmt::Binary::fmt(&val, f) // delegate to i32's implementation
 ///     }
 /// }
 ///
@@ -771,7 +771,7 @@ pub trait Binary {
 ///     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
 ///         let val = self.0;
 ///
-///         write!(f, "{:x}", val) // delegate to i32's implementation
+///         fmt::LowerHex::fmt(&val, f) // delegate to i32's implementation
 ///     }
 /// }
 ///
@@ -824,7 +824,7 @@ pub trait LowerHex {
 ///     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
 ///         let val = self.0;
 ///
-///         write!(f, "{:X}", val) // delegate to i32's implementation
+///         fmt::UpperHex::fmt(&val, f) // delegate to i32's implementation
 ///     }
 /// }
 ///
@@ -869,7 +869,8 @@ pub trait UpperHex {
 ///     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
 ///         // use `as` to convert to a `*const T`, which implements Pointer, which we can use
 ///
-///         write!(f, "{:p}", self as *const Length)
+///         let ptr = self as *const Self;
+///         fmt::Pointer::fmt(&ptr, f)
 ///     }
 /// }
 ///

src/libcore/iter/traits/collect.rs

@@ -91,9 +91,9 @@
 /// ```
 #[stable(feature = "rust1", since = "1.0.0")]
 #[rustc_on_unimplemented(
-    message="a collection of type `{Self}` cannot be built from an iterator \
+    message="a value of type `{Self}` cannot be built from an iterator \
              over elements of type `{A}`",
-    label="a collection of type `{Self}` cannot be built from `std::iter::Iterator<Item={A}>`",
+    label="value of type `{Self}` cannot be built from `std::iter::Iterator<Item={A}>`",
 )]
 pub trait FromIterator<A>: Sized {
     /// Creates a value from an iterator.

src/librustc_error_codes/error_codes.rs

@@ -347,6 +347,7 @@ E0622: include_str!("./error_codes/E0622.md"),
 E0623: include_str!("./error_codes/E0623.md"),
 E0624: include_str!("./error_codes/E0624.md"),
 E0626: include_str!("./error_codes/E0626.md"),
+E0631: include_str!("./error_codes/E0631.md"),
 E0633: include_str!("./error_codes/E0633.md"),
 E0635: include_str!("./error_codes/E0635.md"),
 E0636: include_str!("./error_codes/E0636.md"),
@@ -580,7 +581,6 @@ E0745: include_str!("./error_codes/E0745.md"),
     // rustc_const_unstable attribute must be paired with stable/unstable
     // attribute
     E0630,
-    E0631, // type mismatch in closure arguments
     E0632, // cannot provide explicit generic arguments when `impl Trait` is
            // used in argument position
     E0634, // type has conflicting packed representaton hints

src/librustc_error_codes/error_codes/E0092.md

@@ -1,4 +1,5 @@
-You tried to declare an undefined atomic operation function.
+An undefined atomic operation function was declared.
+
 Erroneous code example:
 
 ```compile_fail,E0092
@@ -11,8 +12,8 @@ extern "rust-intrinsic" {
 ```
 
 Please check you didn't make a mistake in the function's name. All intrinsic
-functions are defined in librustc_codegen_llvm/intrinsic.rs and in
-libcore/intrinsics.rs in the Rust source code. Example:
+functions are defined in `librustc_codegen_llvm/intrinsic.rs` and in
+`libcore/intrinsics.rs` in the Rust source code. Example:
 
 ```
 #![feature(intrinsics)]

src/librustc_error_codes/error_codes/E0093.md

@@ -1,4 +1,6 @@
-You declared an unknown intrinsic function. Erroneous code example:
+An unknown intrinsic function was declared.
+
+Erroneous code example:
 
 ```compile_fail,E0093
 #![feature(intrinsics)]
@@ -15,8 +17,8 @@ fn main() {
 ```
 
 Please check you didn't make a mistake in the function's name. All intrinsic
-functions are defined in librustc_codegen_llvm/intrinsic.rs and in
-libcore/intrinsics.rs in the Rust source code. Example:
+functions are defined in `librustc_codegen_llvm/intrinsic.rs` and in
+`libcore/intrinsics.rs` in the Rust source code. Example:
 
 ```
 #![feature(intrinsics)]

src/librustc_error_codes/error_codes/E0094.md

@@ -1,4 +1,5 @@
-You gave an invalid number of type parameters to an intrinsic function.
+An invalid number of type parameters was given to an intrinsic function.
+
 Erroneous code example:
 
 ```compile_fail,E0094

src/librustc_error_codes/error_codes/E0106.md

@@ -2,7 +2,7 @@ This error indicates that a lifetime is missing from a type. If it is an error
 inside a function signature, the problem may be with failing to adhere to the
 lifetime elision rules (see below).
 
-Here are some simple examples of where you'll run into this error:
+Erroneous code examples:
 
 ```compile_fail,E0106
 struct Foo1 { x: &bool }
@@ -27,7 +27,7 @@ function signatures which allows you to leave out lifetimes in certain cases.
 For more background on lifetime elision see [the book][book-le].
 
 The lifetime elision rules require that any function signature with an elided
-output lifetime must either have
+output lifetime must either have:
 
  - exactly one input lifetime
  - or, multiple input lifetimes, but the function must also be a method with a

src/librustc_error_codes/error_codes/E0107.md

@@ -1,4 +1,6 @@
-This error means that an incorrect number of generic arguments were provided:
+An incorrect number of generic arguments were provided.
+
+Erroneous code example:
 
 ```compile_fail,E0107
 struct Foo<T> { x: T }
@@ -9,19 +11,34 @@ struct Baz<S, T> { x: Foo<S, T> } // error: wrong number of type arguments:
                                   //        expected 1, found 2
 
 fn foo<T, U>(x: T, y: U) {}
+fn f() {}
 
 fn main() {
     let x: bool = true;
     foo::<bool>(x);                 // error: wrong number of type arguments:
                                     //        expected 2, found 1
     foo::<bool, i32, i32>(x, 2, 4); // error: wrong number of type arguments:
                                     //        expected 2, found 3
+    f::<'static>();                 // error: wrong number of lifetime arguments
+                                    //        expected 0, found 1
 }
+```
+
+When using/declaring an item with generic arguments, you must provide the exact
+same number:
+
+```
+struct Foo<T> { x: T }
+
+struct Bar<T> { x: Foo<T> }               // ok!
+struct Baz<S, T> { x: Foo<S>, y: Foo<T> } // ok!
 
+fn foo<T, U>(x: T, y: U) {}
 fn f() {}
 
 fn main() {
-    f::<'static>(); // error: wrong number of lifetime arguments:
-                    //        expected 0, found 1
+    let x: bool = true;
+    foo::<bool, u32>(x, 12);              // ok!
+    f();                                  // ok!
 }
 ```