| #![feature(rustc_attrs)] |
| #![warn(clippy::eager_transmute)] |
| #![allow(clippy::transmute_int_to_non_zero)] |
| |
| use std::num::NonZeroU8; |
| |
| #[repr(u8)] |
| enum Opcode { |
| Add = 0, |
| Sub = 1, |
| Mul = 2, |
| Div = 3, |
| } |
| |
| struct Data { |
| foo: &'static [u8], |
| bar: &'static [u8], |
| } |
| |
| fn int_to_opcode(op: u8) -> Option<Opcode> { |
| (op < 4).then(|| unsafe { std::mem::transmute(op) }) |
| } |
| |
| fn f(op: u8, op2: Data, unrelated: u8) { |
| true.then_some(unsafe { std::mem::transmute::<_, Opcode>(op) }); |
| (unrelated < 4).then_some(unsafe { std::mem::transmute::<_, Opcode>(op) }); |
| (op < 4).then(|| unsafe { std::mem::transmute::<_, Opcode>(op) }); |
| (op > 4).then(|| unsafe { std::mem::transmute::<_, Opcode>(op) }); |
| (op == 0).then(|| unsafe { std::mem::transmute::<_, Opcode>(op) }); |
| |
| let _: Option<Opcode> = (op > 0 && op < 10).then(|| unsafe { std::mem::transmute(op) }); |
| let _: Option<Opcode> = (op > 0 && op < 10 && unrelated == 0).then(|| unsafe { std::mem::transmute(op) }); |
| |
| // lint even when the transmutable goes through field/array accesses |
| let _: Option<Opcode> = (op2.foo[0] > 0 && op2.foo[0] < 10).then(|| unsafe { std::mem::transmute(op2.foo[0]) }); |
| |
| // don't lint: wrong index used in the transmute |
| let _: Option<Opcode> = (op2.foo[0] > 0 && op2.foo[0] < 10).then_some(unsafe { std::mem::transmute(op2.foo[1]) }); |
| |
| // don't lint: no check for the transmutable in the condition |
| let _: Option<Opcode> = (op2.foo[0] > 0 && op2.bar[1] < 10).then_some(unsafe { std::mem::transmute(op2.bar[0]) }); |
| |
| // don't lint: wrong variable |
| let _: Option<Opcode> = (op2.foo[0] > 0 && op2.bar[1] < 10).then_some(unsafe { std::mem::transmute(op) }); |
| |
| // range contains checks |
| let _: Option<Opcode> = (1..=3).contains(&op).then(|| unsafe { std::mem::transmute(op) }); |
| let _: Option<Opcode> = ((1..=3).contains(&op) || op == 4).then(|| unsafe { std::mem::transmute(op) }); |
| let _: Option<Opcode> = (1..3).contains(&op).then(|| unsafe { std::mem::transmute(op) }); |
| let _: Option<Opcode> = (1..).contains(&op).then(|| unsafe { std::mem::transmute(op) }); |
| let _: Option<Opcode> = (..3).contains(&op).then(|| unsafe { std::mem::transmute(op) }); |
| let _: Option<Opcode> = (..=3).contains(&op).then(|| unsafe { std::mem::transmute(op) }); |
| |
| // unrelated binding in contains |
| let _: Option<Opcode> = (1..=3) |
| .contains(&unrelated) |
| .then_some(unsafe { std::mem::transmute(op) }); |
| } |
| |
| unsafe fn f2(op: u8) { |
| (op < 4).then(|| std::mem::transmute::<_, Opcode>(op)); |
| } |
| |
| #[rustc_layout_scalar_valid_range_end(254)] |
| struct NonMaxU8(u8); |
| #[rustc_layout_scalar_valid_range_end(254)] |
| #[rustc_layout_scalar_valid_range_start(1)] |
| struct NonZeroNonMaxU8(u8); |
| |
| macro_rules! impls { |
| ($($t:ty),*) => { |
| $( |
| impl PartialEq<u8> for $t { |
| fn eq(&self, other: &u8) -> bool { |
| self.0 == *other |
| } |
| } |
| impl PartialOrd<u8> for $t { |
| fn partial_cmp(&self, other: &u8) -> Option<std::cmp::Ordering> { |
| self.0.partial_cmp(other) |
| } |
| } |
| )* |
| }; |
| } |
| impls!(NonMaxU8, NonZeroNonMaxU8); |
| |
| fn niche_tests(v1: u8, v2: NonZeroU8, v3: NonZeroNonMaxU8) { |
| // u8 -> NonZeroU8, do lint |
| let _: Option<NonZeroU8> = (v1 > 0).then(|| unsafe { std::mem::transmute(v1) }); |
| |
| // NonZeroU8 -> u8, don't lint, target type has no niche and therefore a higher validity range |
| let _: Option<u8> = (v2 > NonZeroU8::new(1).unwrap()).then_some(unsafe { std::mem::transmute(v2) }); |
| |
| // NonZeroU8 -> NonMaxU8, do lint, different niche |
| let _: Option<NonMaxU8> = (v2 < NonZeroU8::new(255).unwrap()).then(|| unsafe { std::mem::transmute(v2) }); |
| |
| // NonZeroNonMaxU8 -> NonMaxU8, don't lint, target type has more validity |
| let _: Option<NonMaxU8> = (v3 < 255).then_some(unsafe { std::mem::transmute(v2) }); |
| |
| // NonZeroU8 -> NonZeroNonMaxU8, do lint, target type has less validity |
| let _: Option<NonZeroNonMaxU8> = (v2 < NonZeroU8::new(255).unwrap()).then(|| unsafe { std::mem::transmute(v2) }); |
| } |
| |
| fn main() {} |