#![feature(intrinsics)] // Directly call intrinsic to avoid debug assertions in libstd extern "rust-intrinsic" { fn copy_nonoverlapping(src: *const T, dst: *mut T, count: usize); } fn main() { let mut data = [0u8; 16]; unsafe { let a = data.as_mut_ptr(); let b = a.wrapping_offset(1) as *mut _; copy_nonoverlapping(a, b, 2); //~ ERROR: copy_nonoverlapping called on overlapping ranges } }