| #[repr(packed)] |
| pub struct Good { |
| data: u64, |
| ptr: &'static u64, |
| data2: [u64; 2], |
| aligned: [u8; 32], |
| } |
| |
| #[repr(packed(2))] |
| pub struct Packed2 { |
| x: u32, |
| y: u16, |
| z: u8, |
| } |
| |
| trait Foo { |
| fn evil(&self); |
| } |
| |
| // Test for #108122 |
| #[automatically_derived] |
| impl Foo for Packed2 { |
| fn evil(&self) { |
| unsafe { |
| &self.x; //~ ERROR reference to packed field |
| } |
| } |
| } |
| |
| fn main() { |
| unsafe { |
| let good = Good { data: 0, ptr: &0, data2: [0, 0], aligned: [0; 32] }; |
| |
| let _ = &good.ptr; //~ ERROR reference to packed field |
| let _ = &good.data; //~ ERROR reference to packed field |
| // Error even when turned into raw pointer immediately. |
| let _ = &good.data as *const _; //~ ERROR reference to packed field |
| let _: *const _ = &good.data; //~ ERROR reference to packed field |
| // Error on method call. |
| let _ = good.data.clone(); //~ ERROR reference to packed field |
| // Error for nested fields. |
| let _ = &good.data2[0]; //~ ERROR reference to packed field |
| |
| let _ = &*good.ptr; // ok, behind a pointer |
| let _ = &good.aligned; // ok, has align 1 |
| let _ = &good.aligned[2]; // ok, has align 1 |
| } |
| |
| unsafe { |
| let packed2 = Packed2 { x: 0, y: 0, z: 0 }; |
| let _ = &packed2.x; //~ ERROR reference to packed field |
| let _ = &packed2.y; // ok, has align 2 in packed(2) struct |
| let _ = &packed2.z; // ok, has align 1 |
| packed2.evil(); |
| } |
| |
| unsafe { |
| struct U16(u16); |
| |
| impl Drop for U16 { |
| fn drop(&mut self) { |
| println!("{:p}", self); |
| } |
| } |
| |
| struct HasDrop; |
| |
| impl Drop for HasDrop { |
| fn drop(&mut self) {} |
| } |
| |
| #[allow(unused)] |
| struct Wrapper { |
| a: U16, |
| b: HasDrop, |
| } |
| #[allow(unused)] |
| #[repr(packed(2))] |
| struct Wrapper2 { |
| a: U16, |
| b: HasDrop, |
| } |
| |
| // An outer struct with more restrictive packing than the inner struct -- make sure we |
| // notice that! |
| #[repr(packed)] |
| struct Misalign<T>(u8, T); |
| |
| let m1 = Misalign(0, Wrapper { a: U16(10), b: HasDrop }); |
| let _ref = &m1.1.a; //~ ERROR reference to packed field |
| |
| let m2 = Misalign(0, Wrapper2 { a: U16(10), b: HasDrop }); |
| let _ref = &m2.1.a; //~ ERROR reference to packed field |
| } |
| } |