//@compile-flags: -Zmiri-permissive-provenance use std::mem; use std::ptr; fn eq_ref(x: &T, y: &T) -> bool { x as *const _ == y as *const _ } fn f() -> i32 { 42 } fn ptr_int_casts() { // int-ptr-int assert_eq!(1 as *const i32 as usize, 1); assert_eq!((1 as *const i32).wrapping_offset(4) as usize, 1 + 4 * 4); // negative overflowing wrapping_offset (going through memory because // this used to trigger an ICE on 32bit) let val = &mut ptr::null(); *val = (1 as *const u8).wrapping_offset(-4); assert_eq!(*val as usize, usize::MAX - 2); // ptr-int-ptr { let x = 13; let mut y = &x as &_ as *const _ as usize; y += 13; y -= 13; let y = y as *const _; assert!(eq_ref(&x, unsafe { &*y })); } // fnptr-int-fnptr { let x: fn() -> i32 = f; let y: *mut u8 = unsafe { mem::transmute(x as fn() -> i32) }; let mut y = y as usize; y += 13; y -= 13; let x: fn() -> i32 = unsafe { mem::transmute(y as *mut u8) }; assert_eq!(x(), 42); } // involving types other than usize assert_eq!((-1i32) as usize as *const i32 as usize, (-1i32) as usize); } fn ptr_int_ops() { let v = [1i16, 2]; let x = &v[1] as *const i16 as usize; // arithmetic let _y = x + 4; let _y = 4 + x; let _y = x - 2; // bit-operations, covered by alignment assert_eq!(x & 1, 0); assert_eq!(x & 0, 0); assert_eq!(1 & (x + 1), 1); let _y = !1 & x; let _y = !0 & x; let _y = x & !1; // remainder, covered by alignment assert_eq!(x % 2, 0); assert_eq!((x + 1) % 2, 1); // remainder with 1 is always 0 assert_eq!(x % 1, 0); } fn main() { ptr_int_casts(); ptr_int_ops(); }