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//! Ensure that unstable intrinsics can actually not be called,
//! neither within a crate nor cross-crate.
//@ aux-build:unstable_intrinsic.rs
#![feature(staged_api, rustc_attrs, intrinsics)]
#![stable(since="1.0.0", feature = "stable")]
#![feature(local)]
extern crate unstable_intrinsic;
fn main() {
const_main();
}
const fn const_main() {
let x = 42;
unsafe {
unstable_intrinsic::size_of_val(&x);
//~^ERROR: unstable library feature `unstable`
//~|ERROR: not yet stable as a const intrinsic
unstable_intrinsic::min_align_of_val(&x);
//~^ERROR: unstable library feature `unstable`
//~|ERROR: not yet stable as a const intrinsic
size_of_val(&x);
//~^ERROR: cannot use `#[feature(local)]`
min_align_of_val(&x);
//~^ERROR: cannot use `#[feature(local)]`
}
}
#[unstable(feature = "local", issue = "42")]
#[rustc_intrinsic]
#[rustc_intrinsic_must_be_overridden]
pub const unsafe fn size_of_val<T>(x: *const T) -> usize { 42 }
#[unstable(feature = "local", issue = "42")]
#[rustc_const_unstable(feature = "local", issue = "42")]
#[rustc_intrinsic]
#[rustc_intrinsic_must_be_overridden]
pub const unsafe fn min_align_of_val<T>(x: *const T) -> usize { 42 }
#[stable(feature = "rust1", since = "1.0.0")]
#[rustc_const_stable(feature = "const_intrinsic_copy", since = "1.63.0")]
#[inline]
pub const unsafe fn copy<T>(src: *const T, dst: *mut T, count: usize) {
// Const stability attributes are not inherited from parent items.
#[rustc_intrinsic]
#[rustc_intrinsic_must_be_overridden]
const unsafe fn copy<T>(src: *const T, dst: *mut T, count: usize) {
unimplemented!()
}
unsafe { copy(src, dst, count) }
//~^ ERROR cannot be (indirectly) exposed to stable
}
// Ensure that a fallback body is recursively-const-checked.
mod fallback {
#[rustc_intrinsic]
const unsafe fn copy<T>(src: *const T, _dst: *mut T, _count: usize) {
super::size_of_val(src);
//~^ ERROR cannot use `#[feature(local)]`
}
}
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