Auto merge of #63607 - Centril:rollup-yry7nsw, r=Centril

Rollup of 5 pull requests

Successful merges:

 - #63173 (Use libunwind from llvm-project submodule for musl targets)
 - #63462 (Opaque builtin derive macros)
 - #63539 (Suggest Rust 2018 on `<expr>.await` with no such field)
 - #63545 (Feature gate 'yield $expr?' pre-expansion)
 - #63584 (libcore: more cleanups using `#![feature(associated_type_bounds)]`)

Failed merges:

r? @ghost

Author: bors

src/bootstrap/sanity.rs

@@ -202,10 +202,6 @@ pub fn check(build: &mut Build) {
                         panic!("couldn't find libc.a in musl dir: {}",
                                root.join("lib").display());
                     }
-                    if fs::metadata(root.join("lib/libunwind.a")).is_err() {
-                        panic!("couldn't find libunwind.a in musl dir: {}",
-                               root.join("lib").display());
-                    }
                 }
                 None => {
                     panic!("when targeting MUSL either the rust.musl-root \

src/ci/docker/scripts/musl-toolchain.sh

@@ -54,29 +54,3 @@ if [ "$REPLACE_CC" = "1" ]; then
         ln -s $TARGET-g++ /usr/local/bin/$exec
     done
 fi
-
-export CC=$TARGET-gcc
-export CXX=$TARGET-g++
-
-LLVM=70
-
-# may have been downloaded in a previous run
-if [ ! -d libunwind-release_$LLVM ]; then
-  curl -L https://github.com/llvm-mirror/llvm/archive/release_$LLVM.tar.gz | tar xzf -
-  curl -L https://github.com/llvm-mirror/libunwind/archive/release_$LLVM.tar.gz | tar xzf -
-fi
-
-# fixme(mati865): Replace it with https://github.com/rust-lang/rust/pull/59089
-mkdir libunwind-build
-cd libunwind-build
-cmake ../libunwind-release_$LLVM \
-          -DLLVM_PATH=/build/llvm-release_$LLVM \
-          -DLIBUNWIND_ENABLE_SHARED=0 \
-          -DCMAKE_C_COMPILER=$CC \
-          -DCMAKE_CXX_COMPILER=$CXX \
-          -DCMAKE_C_FLAGS="$CFLAGS" \
-          -DCMAKE_CXX_FLAGS="$CXXFLAGS"
-
-hide_output make -j$(nproc)
-cp lib/libunwind.a $OUTPUT/$TARGET/lib
-cd - && rm -rf libunwind-build

src/ci/docker/scripts/musl.sh

@@ -20,6 +20,8 @@ exit 1
 TAG=$1
 shift
 
+# Ancient binutils versions don't understand debug symbols produced by more recent tools.
+# Apparently applying `-fPIC` everywhere allows them to link successfully.
 export CFLAGS="-fPIC $CFLAGS"
 
 MUSL=musl-1.1.22
@@ -38,27 +40,3 @@ else
 fi
 hide_output make install
 hide_output make clean
-
-cd ..
-
-LLVM=70
-
-# may have been downloaded in a previous run
-if [ ! -d libunwind-release_$LLVM ]; then
-  curl -L https://github.com/llvm-mirror/llvm/archive/release_$LLVM.tar.gz | tar xzf -
-  curl -L https://github.com/llvm-mirror/libunwind/archive/release_$LLVM.tar.gz | tar xzf -
-fi
-
-mkdir libunwind-build
-cd libunwind-build
-cmake ../libunwind-release_$LLVM \
-          -DLLVM_PATH=/build/llvm-release_$LLVM \
-          -DLIBUNWIND_ENABLE_SHARED=0 \
-          -DCMAKE_C_COMPILER=$CC \
-          -DCMAKE_CXX_COMPILER=$CXX \
-          -DCMAKE_C_FLAGS="$CFLAGS" \
-          -DCMAKE_CXX_FLAGS="$CXXFLAGS"
-
-hide_output make -j$(nproc)
-cp lib/libunwind.a /musl-$TAG/lib
-cd ../ && rm -rf libunwind-build

src/libcore/clone.rs

@@ -135,7 +135,6 @@ pub trait Clone : Sized {
 
 /// Derive macro generating an impl of the trait `Clone`.
 #[rustc_builtin_macro]
-#[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

@@ -202,7 +202,6 @@ pub trait PartialEq<Rhs: ?Sized = Self> {
 
 /// Derive macro generating an impl of the trait `PartialEq`.
 #[rustc_builtin_macro]
-#[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 */ }
@@ -265,7 +264,6 @@ pub trait Eq: PartialEq<Self> {
 
 /// Derive macro generating an impl of the trait `Eq`.
 #[rustc_builtin_macro]
-#[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 */ }
@@ -616,7 +614,6 @@ pub trait Ord: Eq + PartialOrd<Self> {
 
 /// Derive macro generating an impl of the trait `Ord`.
 #[rustc_builtin_macro]
-#[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 */ }
@@ -865,7 +862,6 @@ pub trait PartialOrd<Rhs: ?Sized = Self>: PartialEq<Rhs> {
 
 /// Derive macro generating an impl of the trait `PartialOrd`.
 #[rustc_builtin_macro]
-#[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]
-#[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/builders.rs

@@ -98,7 +98,7 @@ pub struct DebugStruct<'a, 'b: 'a> {
     has_fields: bool,
 }
 
-pub fn debug_struct_new<'a, 'b>(fmt: &'a mut fmt::Formatter<'b>,
+pub(super) fn debug_struct_new<'a, 'b>(fmt: &'a mut fmt::Formatter<'b>,
                                 name: &str)
                                 -> DebugStruct<'a, 'b> {
     let result = fmt.write_str(name);
@@ -251,7 +251,10 @@ pub struct DebugTuple<'a, 'b: 'a> {
     empty_name: bool,
 }
 
-pub fn debug_tuple_new<'a, 'b>(fmt: &'a mut fmt::Formatter<'b>, name: &str) -> DebugTuple<'a, 'b> {
+pub(super) fn debug_tuple_new<'a, 'b>(
+    fmt: &'a mut fmt::Formatter<'b>,
+    name: &str,
+) -> DebugTuple<'a, 'b> {
     let result = fmt.write_str(name);
     DebugTuple {
         fmt,
@@ -418,7 +421,7 @@ pub struct DebugSet<'a, 'b: 'a> {
     inner: DebugInner<'a, 'b>,
 }
 
-pub fn debug_set_new<'a, 'b>(fmt: &'a mut fmt::Formatter<'b>) -> DebugSet<'a, 'b> {
+pub(super) fn debug_set_new<'a, 'b>(fmt: &'a mut fmt::Formatter<'b>) -> DebugSet<'a, 'b> {
     let result = fmt.write_str("{");
     DebugSet {
         inner: DebugInner {
@@ -555,7 +558,7 @@ pub struct DebugList<'a, 'b: 'a> {
     inner: DebugInner<'a, 'b>,
 }
 
-pub fn debug_list_new<'a, 'b>(fmt: &'a mut fmt::Formatter<'b>) -> DebugList<'a, 'b> {
+pub(super) fn debug_list_new<'a, 'b>(fmt: &'a mut fmt::Formatter<'b>) -> DebugList<'a, 'b> {
     let result = fmt.write_str("[");
     DebugList {
         inner: DebugInner {
@@ -697,7 +700,7 @@ pub struct DebugMap<'a, 'b: 'a> {
     state: PadAdapterState,
 }
 
-pub fn debug_map_new<'a, 'b>(fmt: &'a mut fmt::Formatter<'b>) -> DebugMap<'a, 'b> {
+pub(super) fn debug_map_new<'a, 'b>(fmt: &'a mut fmt::Formatter<'b>) -> DebugMap<'a, 'b> {
     let result = fmt.write_str("{");
     DebugMap {
         fmt,

src/libcore/fmt/mod.rs

@@ -549,7 +549,6 @@ pub trait Debug {
 pub(crate) mod macros {
     /// Derive macro generating an impl of the trait `Debug`.
     #[rustc_builtin_macro]
-    #[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]
-    #[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/iter/adapters/flatten.rs

@@ -72,8 +72,7 @@ impl<I: Iterator, U: IntoIterator, F> Iterator for FlatMap<I, U, F>
 impl<I: DoubleEndedIterator, U, F> DoubleEndedIterator for FlatMap<I, U, F>
 where
     F: FnMut(I::Item) -> U,
-    U: IntoIterator,
-    U::IntoIter: DoubleEndedIterator,
+    U: IntoIterator<IntoIter: DoubleEndedIterator>,
 {
     #[inline]
     fn next_back(&mut self) -> Option<U::Item> { self.inner.next_back() }
@@ -107,10 +106,7 @@ impl<I, U, F> FusedIterator for FlatMap<I, U, F>
 /// [`Iterator`]: trait.Iterator.html
 #[must_use = "iterators are lazy and do nothing unless consumed"]
 #[stable(feature = "iterator_flatten", since = "1.29.0")]
-pub struct Flatten<I: Iterator>
-where
-    I::Item: IntoIterator,
-{
+pub struct Flatten<I: Iterator<Item: IntoIterator>> {
     inner: FlattenCompat<I, <I::Item as IntoIterator>::IntoIter>,
 }