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type Field1 = i32;
type Field2 = f32;
type Field3 = i64;
#[repr(C)]
union DummyUnion {
field1: Field1,
field2: Field2,
field3: Field3,
}
const FLOAT1_AS_I32: i32 = 1065353216;
const UNION: DummyUnion = DummyUnion { field1: FLOAT1_AS_I32 };
const fn read_field1() -> Field1 {
const FIELD1: Field1 = unsafe { UNION.field1 };
FIELD1
}
const fn read_field2() -> Field2 {
const FIELD2: Field2 = unsafe { UNION.field2 };
FIELD2
}
const fn read_field3() -> Field3 {
const FIELD3: Field3 = unsafe { UNION.field3 };
//~^ ERROR evaluation of constant value failed
//~| uninitialized
FIELD3
}
fn main() {
assert_eq!(read_field1(), FLOAT1_AS_I32);
assert_eq!(read_field2(), 1.0);
assert_eq!(read_field3(), unsafe { UNION.field3 });
}
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