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// { dg-additional-options "-w" }
#![feature(intrinsics)]
#[lang = "sized"]
pub trait Sized {}
mod intrinsics {
extern "rust-intrinsic" {
pub fn wrapping_add<T>(a: T, b: T) -> T;
pub fn rotate_left<T>(a: T, b: T) -> T;
pub fn rotate_right<T>(a: T, b: T) -> T;
pub fn offset<T>(ptr: *const T, count: isize) -> *const T;
}
}
mod mem {
extern "rust-intrinsic" {
#[rustc_const_stable(feature = "const_transmute", since = "1.46.0")]
pub fn transmute<T, U>(_: T) -> U;
pub fn size_of<T>() -> usize;
}
}
macro_rules! impl_uint {
($($ty:ident = $lang:literal),*) => {
$(
impl $ty {
pub fn wrapping_add(self, rhs: Self) -> Self {
// intrinsics::wrapping_add(self, rhs)
self + rhs
}
pub fn rotate_left(self, n: u32) -> Self {
unsafe {
intrinsics::rotate_left(self, n as Self)
}
}
pub fn rotate_right(self, n: u32) -> Self {
unsafe {
intrinsics::rotate_right(self, n as Self)
}
}
pub fn to_le(self) -> Self {
{
self
}
}
pub const fn from_le_bytes(bytes: [u8; mem::size_of::<Self>()]) -> Self {
// { dg-error "only functions marked as .const. are allowed to be called from constant contexts" "" { target *-*-* } .-1 }
Self::from_le(Self::from_ne_bytes(bytes))
}
pub const fn from_le(x: Self) -> Self {
#[cfg(target_endian = "little")]
{
x
}
}
pub const fn from_ne_bytes(bytes: [u8; mem::size_of::<Self>()]) -> Self {
// { dg-error "only functions marked as .const. are allowed to be called from constant contexts" "" { target *-*-* } .-1 }
unsafe { mem::transmute(bytes) }
}
}
)*
}
}
impl_uint!(
u8 = "u8",
u16 = "u16",
u32 = "u32",
u64 = "u64",
u128 = "u128",
usize = "usize"
);
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