[rustc.git] / compiler / rustc_error_codes / src / error_codes / E0588.md

A type with `packed` representation hint has a field with `align`
representation hint.

Erroneous code example:

```compile_fail,E0588
#[repr(align(16))]
struct Aligned(i32);

#[repr(packed)] // error!
struct Packed(Aligned);
```

Just like you cannot have both `align` and `packed` representation hints on the
same type, a `packed` type cannot contain another type with the `align`
representation hint. However, you can do the opposite:

```
#[repr(packed)]
struct Packed(i32);

#[repr(align(16))] // ok!
struct Aligned(Packed);
```
Commit	Line	Data
60c5eb7d XL	1	A type with `packed` representation hint has a field with `align`
	2	representation hint.
	3
	4	Erroneous code example:
	5
	6	```compile_fail,E0588
	7	#[repr(align(16))]
	8	struct Aligned(i32);
	9
	10	#[repr(packed)] // error!
	11	struct Packed(Aligned);
	12	```
	13
f25598a0	14	Just like you cannot have both `align` and `packed` representation hints on the
60c5eb7d XL	15	same type, a `packed` type cannot contain another type with the `align`
	16	representation hint. However, you can do the opposite:
	17
	18	```
	19	#[repr(packed)]
	20	struct Packed(i32);
	21
	22	#[repr(align(16))] // ok!
	23	struct Aligned(Packed);
	24	```