Merge from rustc

Author: The Miri Cronjob Bot

alloc/src/boxed.rs

@@ -704,7 +704,7 @@ impl<T> Box<[T]> {
     }
 
     /// Constructs a new boxed slice with uninitialized contents. Returns an error if
-    /// the allocation fails
+    /// the allocation fails.
     ///
     /// # Examples
     ///
@@ -739,7 +739,7 @@ impl<T> Box<[T]> {
     }
 
     /// Constructs a new boxed slice with uninitialized contents, with the memory
-    /// being filled with `0` bytes. Returns an error if the allocation fails
+    /// being filled with `0` bytes. Returns an error if the allocation fails.
     ///
     /// See [`MaybeUninit::zeroed`][zeroed] for examples of correct and incorrect usage
     /// of this method.
@@ -831,6 +831,85 @@ impl<T, A: Allocator> Box<[T], A> {
     pub fn new_zeroed_slice_in(len: usize, alloc: A) -> Box<[mem::MaybeUninit<T>], A> {
         unsafe { RawVec::with_capacity_zeroed_in(len, alloc).into_box(len) }
     }
+
+    /// Constructs a new boxed slice with uninitialized contents in the provided allocator. Returns an error if
+    /// the allocation fails.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(allocator_api, new_uninit)]
+    ///
+    /// use std::alloc::System;
+    ///
+    /// let mut values = Box::<[u32], _>::try_new_uninit_slice_in(3, System)?;
+    /// let values = unsafe {
+    ///     // Deferred initialization:
+    ///     values[0].as_mut_ptr().write(1);
+    ///     values[1].as_mut_ptr().write(2);
+    ///     values[2].as_mut_ptr().write(3);
+    ///     values.assume_init()
+    /// };
+    ///
+    /// assert_eq!(*values, [1, 2, 3]);
+    /// # Ok::<(), std::alloc::AllocError>(())
+    /// ```
+    #[unstable(feature = "allocator_api", issue = "32838")]
+    #[inline]
+    pub fn try_new_uninit_slice_in(
+        len: usize,
+        alloc: A,
+    ) -> Result<Box<[mem::MaybeUninit<T>], A>, AllocError> {
+        let ptr = if T::IS_ZST || len == 0 {
+            NonNull::dangling()
+        } else {
+            let layout = match Layout::array::<mem::MaybeUninit<T>>(len) {
+                Ok(l) => l,
+                Err(_) => return Err(AllocError),
+            };
+            alloc.allocate(layout)?.cast()
+        };
+        unsafe { Ok(RawVec::from_raw_parts_in(ptr.as_ptr(), len, alloc).into_box(len)) }
+    }
+
+    /// Constructs a new boxed slice with uninitialized contents in the provided allocator, with the memory
+    /// being filled with `0` bytes. Returns an error if the allocation fails.
+    ///
+    /// See [`MaybeUninit::zeroed`][zeroed] for examples of correct and incorrect usage
+    /// of this method.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(allocator_api, new_uninit)]
+    ///
+    /// use std::alloc::System;
+    ///
+    /// let values = Box::<[u32], _>::try_new_zeroed_slice_in(3, System)?;
+    /// let values = unsafe { values.assume_init() };
+    ///
+    /// assert_eq!(*values, [0, 0, 0]);
+    /// # Ok::<(), std::alloc::AllocError>(())
+    /// ```
+    ///
+    /// [zeroed]: mem::MaybeUninit::zeroed
+    #[unstable(feature = "allocator_api", issue = "32838")]
+    #[inline]
+    pub fn try_new_zeroed_slice_in(
+        len: usize,
+        alloc: A,
+    ) -> Result<Box<[mem::MaybeUninit<T>], A>, AllocError> {
+        let ptr = if T::IS_ZST || len == 0 {
+            NonNull::dangling()
+        } else {
+            let layout = match Layout::array::<mem::MaybeUninit<T>>(len) {
+                Ok(l) => l,
+                Err(_) => return Err(AllocError),
+            };
+            alloc.allocate_zeroed(layout)?.cast()
+        };
+        unsafe { Ok(RawVec::from_raw_parts_in(ptr.as_ptr(), len, alloc).into_box(len)) }
+    }
 }
 
 impl<T, A: Allocator> Box<mem::MaybeUninit<T>, A> {

core/src/lib.rs

@@ -165,6 +165,7 @@
 #![feature(const_unsafecell_get_mut)]
 #![feature(const_waker)]
 #![feature(coverage_attribute)]
+#![feature(do_not_recommend)]
 #![feature(duration_consts_float)]
 #![feature(internal_impls_macro)]
 #![feature(ip)]
@@ -248,6 +249,7 @@
 #![feature(transparent_unions)]
 #![feature(try_blocks)]
 #![feature(unboxed_closures)]
+#![feature(unsized_const_params)]
 #![feature(unsized_fn_params)]
 #![feature(with_negative_coherence)]
 // tidy-alphabetical-end

core/src/marker.rs

@@ -975,31 +975,73 @@ pub trait PointerLike {}
 /// that all fields are also `ConstParamTy`, which implies that recursively, all fields
 /// are `StructuralPartialEq`.
 #[lang = "const_param_ty"]
-#[unstable(feature = "adt_const_params", issue = "95174")]
+#[unstable(feature = "unsized_const_params", issue = "95174")]
 #[diagnostic::on_unimplemented(message = "`{Self}` can't be used as a const parameter type")]
 #[allow(multiple_supertrait_upcastable)]
-pub trait ConstParamTy: StructuralPartialEq + Eq {}
+// We name this differently than the derive macro so that the `adt_const_params` can
+// be used independently of `unsized_const_params` without requiring a full path
+// to the derive macro every time it is used. This should be renamed on stabilization.
+pub trait ConstParamTy_: UnsizedConstParamTy + StructuralPartialEq + Eq {}
 
 /// Derive macro generating an impl of the trait `ConstParamTy`.
 #[rustc_builtin_macro]
+#[allow_internal_unstable(unsized_const_params)]
 #[unstable(feature = "adt_const_params", issue = "95174")]
 pub macro ConstParamTy($item:item) {
     /* compiler built-in */
 }
 
+#[cfg_attr(not(bootstrap), lang = "unsized_const_param_ty")]
+#[unstable(feature = "unsized_const_params", issue = "95174")]
+#[diagnostic::on_unimplemented(message = "`{Self}` can't be used as a const parameter type")]
+/// A marker for types which can be used as types of `const` generic parameters.
+///
+/// Equivalent to [`ConstParamTy_`] except that this is used by
+/// the `unsized_const_params` to allow for fake unstable impls.
+pub trait UnsizedConstParamTy: StructuralPartialEq + Eq {}
+
+/// Derive macro generating an impl of the trait `ConstParamTy`.
+#[cfg(not(bootstrap))]
+#[cfg_attr(not(bootstrap), rustc_builtin_macro)]
+#[cfg_attr(not(bootstrap), allow_internal_unstable(unsized_const_params))]
+#[cfg_attr(not(bootstrap), unstable(feature = "unsized_const_params", issue = "95174"))]
+pub macro UnsizedConstParamTy($item:item) {
+    /* compiler built-in */
+}
+
 // FIXME(adt_const_params): handle `ty::FnDef`/`ty::Closure`
 marker_impls! {
     #[unstable(feature = "adt_const_params", issue = "95174")]
-    ConstParamTy for
+    ConstParamTy_ for
+        usize, u8, u16, u32, u64, u128,
+        isize, i8, i16, i32, i64, i128,
+        bool,
+        char,
+        (),
+        {T: ConstParamTy_, const N: usize} [T; N],
+}
+#[cfg(bootstrap)]
+marker_impls! {
+    #[unstable(feature = "adt_const_params", issue = "95174")]
+    ConstParamTy_ for
+        str,
+        {T: ConstParamTy_} [T],
+        {T: ConstParamTy_ + ?Sized} &T,
+}
+
+marker_impls! {
+    #[unstable(feature = "unsized_const_params", issue = "95174")]
+    UnsizedConstParamTy for
         usize, u8, u16, u32, u64, u128,
         isize, i8, i16, i32, i64, i128,
         bool,
         char,
-        str /* Technically requires `[u8]: ConstParamTy` */,
         (),
-        {T: ConstParamTy, const N: usize} [T; N],
-        {T: ConstParamTy} [T],
-        {T: ?Sized + ConstParamTy} &T,
+        {T: UnsizedConstParamTy, const N: usize} [T; N],
+
+        str,
+        {T: UnsizedConstParamTy} [T],
+        {T: UnsizedConstParamTy + ?Sized} &T,
 }
 
 /// A common trait implemented by all function pointers.

core/src/mem/transmutability.rs

@@ -1,4 +1,4 @@
-use crate::marker::ConstParamTy;
+use crate::marker::{ConstParamTy_, UnsizedConstParamTy};
 
 /// Are values of a type transmutable into values of another type?
 ///
@@ -39,7 +39,9 @@ pub struct Assume {
 }
 
 #[unstable(feature = "transmutability", issue = "99571")]
-impl ConstParamTy for Assume {}
+impl ConstParamTy_ for Assume {}
+#[unstable(feature = "transmutability", issue = "99571")]
+impl UnsizedConstParamTy for Assume {}
 
 impl Assume {
     /// Do not assume that *you* have ensured any safety properties are met.

core/src/option.rs

@@ -2507,6 +2507,7 @@ impl<T> ops::FromResidual for Option<T> {
     }
 }
 
+#[diagnostic::do_not_recommend]
 #[unstable(feature = "try_trait_v2_yeet", issue = "96374")]
 impl<T> ops::FromResidual<ops::Yeet<()>> for Option<T> {
     #[inline]

core/src/result.rs

@@ -1990,7 +1990,7 @@ impl<T, E, F: From<E>> ops::FromResidual<Result<convert::Infallible, E>> for Res
         }
     }
 }
-
+#[diagnostic::do_not_recommend]
 #[unstable(feature = "try_trait_v2_yeet", issue = "96374")]
 impl<T, E, F: From<E>> ops::FromResidual<ops::Yeet<E>> for Result<T, F> {
     #[inline]

core/src/tuple.rs

@@ -1,8 +1,9 @@
 // See core/src/primitive_docs.rs for documentation.
 
 use crate::cmp::Ordering::{self, *};
-use crate::marker::ConstParamTy;
+use crate::marker::ConstParamTy_;
 use crate::marker::StructuralPartialEq;
+use crate::marker::UnsizedConstParamTy;
 
 // Recursive macro for implementing n-ary tuple functions and operations
 //
@@ -49,8 +50,15 @@ macro_rules! tuple_impls {
 
         maybe_tuple_doc! {
             $($T)+ @
-            #[unstable(feature = "structural_match", issue = "31434")]
-            impl<$($T: ConstParamTy),+> ConstParamTy for ($($T,)+)
+            #[unstable(feature = "adt_const_params", issue = "95174")]
+            impl<$($T: ConstParamTy_),+> ConstParamTy_ for ($($T,)+)
+            {}
+        }
+
+        maybe_tuple_doc! {
+            $($T)+ @
+            #[unstable(feature = "unsized_const_params", issue = "95174")]
+            impl<$($T: UnsizedConstParamTy),+> UnsizedConstParamTy for ($($T,)+)
             {}
         }
 

panic_unwind/src/seh.rs

@@ -157,7 +157,10 @@ mod imp {
             // going to be cross-lang LTOed anyway. However, using expose is shorter and
             // requires less unsafe.
             let addr: usize = ptr.expose_provenance();
+            #[cfg(bootstrap)]
             let image_base = unsafe { addr_of!(__ImageBase) }.addr();
+            #[cfg(not(bootstrap))]
+            let image_base = addr_of!(__ImageBase).addr();
             let offset: usize = addr - image_base;
             Self(offset as u32)
         }
@@ -250,7 +253,10 @@ extern "C" {
 // This is fine since the MSVC runtime uses string comparison on the type name
 // to match TypeDescriptors rather than pointer equality.
 static mut TYPE_DESCRIPTOR: _TypeDescriptor = _TypeDescriptor {
+    #[cfg(bootstrap)]
     pVFTable: unsafe { addr_of!(TYPE_INFO_VTABLE) } as *const _,
+    #[cfg(not(bootstrap))]
+    pVFTable: addr_of!(TYPE_INFO_VTABLE) as *const _,
     spare: core::ptr::null_mut(),
     name: TYPE_NAME,
 };

std/Cargo.toml

@@ -20,8 +20,12 @@ core = { path = "../core", public = true }
 compiler_builtins = { version = "0.1.105" }
 profiler_builtins = { path = "../profiler_builtins", optional = true }
 unwind = { path = "../unwind" }
-hashbrown = { version = "0.14", default-features = false, features = ['rustc-dep-of-std'] }
-std_detect = { path = "../stdarch/crates/std_detect", default-features = false, features = ['rustc-dep-of-std'] }
+hashbrown = { version = "0.14", default-features = false, features = [
+    'rustc-dep-of-std',
+] }
+std_detect = { path = "../stdarch/crates/std_detect", default-features = false, features = [
+    'rustc-dep-of-std',
+] }
 
 # Dependencies of the `backtrace` crate
 rustc-demangle = { version = "0.1.24", features = ['rustc-dep-of-std'] }
@@ -31,13 +35,27 @@ miniz_oxide = { version = "0.7.0", optional = true, default-features = false }
 addr2line = { version = "0.22.0", optional = true, default-features = false }
 
 [target.'cfg(not(all(windows, target_env = "msvc")))'.dependencies]
-libc = { version = "0.2.153", default-features = false, features = ['rustc-dep-of-std'], public = true }
+libc = { version = "0.2.153", default-features = false, features = [
+    'rustc-dep-of-std',
+], public = true }
 
 [target.'cfg(all(not(target_os = "aix"), not(all(windows, target_env = "msvc", not(target_vendor = "uwp")))))'.dependencies]
-object = { version = "0.36.0", default-features = false, optional = true, features = ['read_core', 'elf', 'macho', 'pe', 'unaligned', 'archive'] }
+object = { version = "0.36.0", default-features = false, optional = true, features = [
+    'read_core',
+    'elf',
+    'macho',
+    'pe',
+    'unaligned',
+    'archive',
+] }
 
 [target.'cfg(target_os = "aix")'.dependencies]
-object = { version = "0.36.0", default-features = false, optional = true, features = ['read_core', 'xcoff', 'unaligned', 'archive'] }
+object = { version = "0.36.0", default-features = false, optional = true, features = [
+    'read_core',
+    'xcoff',
+    'unaligned',
+    'archive',
+] }
 
 [dev-dependencies]
 rand = { version = "0.8.5", default-features = false, features = ["alloc"] }
@@ -47,23 +65,29 @@ rand_xorshift = "0.3.0"
 dlmalloc = { version = "0.2.4", features = ['rustc-dep-of-std'] }
 
 [target.x86_64-fortanix-unknown-sgx.dependencies]
-fortanix-sgx-abi = { version = "0.5.0", features = ['rustc-dep-of-std'], public = true }
+fortanix-sgx-abi = { version = "0.5.0", features = [
+    'rustc-dep-of-std',
+], public = true }
 
 [target.'cfg(target_os = "hermit")'.dependencies]
-hermit-abi = { version = "0.4.0", features = ['rustc-dep-of-std'], public = true }
+hermit-abi = { version = "0.4.0", features = [
+    'rustc-dep-of-std',
+], public = true }
 
 [target.'cfg(target_os = "wasi")'.dependencies]
-wasi = { version = "0.11.0", features = ['rustc-dep-of-std'], default-features = false }
+wasi = { version = "0.11.0", features = [
+    'rustc-dep-of-std',
+], default-features = false }
 
 [target.'cfg(target_os = "uefi")'.dependencies]
-r-efi = { version = "4.2.0", features = ['rustc-dep-of-std'] }
+r-efi = { version = "4.5.0", features = ['rustc-dep-of-std'] }
 r-efi-alloc = { version = "1.0.0", features = ['rustc-dep-of-std'] }
 
 [features]
 backtrace = [
-  'addr2line/rustc-dep-of-std',
-  'object/rustc-dep-of-std',
-  'miniz_oxide/rustc-dep-of-std',
+    'addr2line/rustc-dep-of-std',
+    'object/rustc-dep-of-std',
+    'miniz_oxide/rustc-dep-of-std',
 ]
 
 panic-unwind = ["panic_unwind"]
@@ -77,7 +101,10 @@ llvm-libunwind = ["unwind/llvm-libunwind"]
 system-llvm-libunwind = ["unwind/system-llvm-libunwind"]
 
 # Make panics and failed asserts immediately abort without formatting any message
-panic_immediate_abort = ["core/panic_immediate_abort", "alloc/panic_immediate_abort"]
+panic_immediate_abort = [
+    "core/panic_immediate_abort",
+    "alloc/panic_immediate_abort",
+]
 # Choose algorithms that are optimized for binary size instead of runtime performance
 optimize_for_size = ["core/optimize_for_size", "alloc/optimize_for_size"]
 
@@ -97,6 +124,11 @@ threads = 125
 # Maximum heap size
 heap_size = 0x8000000
 
+[[test]]
+name = "pipe-subprocess"
+path = "tests/pipe_subprocess.rs"
+harness = false
+
 [[bench]]
 name = "stdbenches"
 path = "benches/lib.rs"