src/test/ui/layout/homogeneous-aggr-zero-sized-repr-rust.rs

   1 #![feature(rustc_attrs)]
   2
   3 // Regression test for #56877. We want to ensure that the presence of
   4 // `PhantomData` does not prevent `Bar` from being considered a
   5 // homogeneous aggregate.
   6
   7 #[repr(C)]
   8 pub struct BaseCase {
   9     pub a: f32,
  10     pub b: f32,
  11 }
  12
  13 #[repr(C)]
  14 pub struct WithPhantomData {
  15     pub a: f32,
  16     pub b: f32,
  17     pub _unit: std::marker::PhantomData<()>,
  18 }
  19
  20 pub struct EmptyRustStruct {
  21 }
  22
  23 #[repr(C)]
  24 pub struct WithEmptyRustStruct {
  25     pub a: f32,
  26     pub b: f32,
  27     pub _unit: EmptyRustStruct,
  28 }
  29
  30 pub struct TransitivelyEmptyRustStruct {
  31     field: EmptyRustStruct,
  32     array: [u32; 0],
  33 }
  34
  35 #[repr(C)]
  36 pub struct WithTransitivelyEmptyRustStruct {
  37     pub a: f32,
  38     pub b: f32,
  39     pub _unit: TransitivelyEmptyRustStruct,
  40 }
  41
  42 pub enum EmptyRustEnum {
  43     Dummy,
  44 }
  45
  46 #[repr(C)]
  47 pub struct WithEmptyRustEnum {
  48     pub a: f32,
  49     pub b: f32,
  50     pub _unit: EmptyRustEnum,
  51 }
  52
  53 #[rustc_layout(homogeneous_aggregate)]
  54 pub type Test1 = BaseCase;
  55 //~^ ERROR homogeneous_aggregate: Ok(Homogeneous(Reg { kind: Float, size: Size { raw: 4 } }))
  56
  57 #[rustc_layout(homogeneous_aggregate)]
  58 pub type Test2 = WithPhantomData;
  59 //~^ ERROR homogeneous_aggregate: Ok(Homogeneous(Reg { kind: Float, size: Size { raw: 4 } }))
  60
  61 #[rustc_layout(homogeneous_aggregate)]
  62 pub type Test3 = WithEmptyRustStruct;
  63 //~^ ERROR homogeneous_aggregate: Ok(Homogeneous(Reg { kind: Float, size: Size { raw: 4 } }))
  64
  65 #[rustc_layout(homogeneous_aggregate)]
  66 pub type Test4 = WithTransitivelyEmptyRustStruct;
  67 //~^ ERROR homogeneous_aggregate: Ok(Homogeneous(Reg { kind: Float, size: Size { raw: 4 } }))
  68
  69 #[rustc_layout(homogeneous_aggregate)]
  70 pub type Test5 = WithEmptyRustEnum;
  71 //~^ ERROR homogeneous_aggregate: Ok(Homogeneous(Reg { kind: Float, size: Size { raw: 4 } }))
  72
  73 fn main() { }