[rustc.git] / compiler / rustc_error_codes / src / error_codes / E0544.md

Multiple stability attributes were declared on the same item.

Erroneous code example:

```compile_fail,E0544
#![feature(staged_api)]
#![stable(since = "1.0.0", feature = "rust1")]

#[stable(feature = "rust1", since = "1.0.0")]
#[stable(feature = "test", since = "2.0.0")] // invalid
fn foo() {}
```

To fix this issue, ensure that each item has at most one stability attribute.

```
#![feature(staged_api)]
#![stable(since = "1.0.0", feature = "rust1")]

#[stable(feature = "test", since = "2.0.0")] // ok!
fn foo() {}
```

See the [How Rust is Made and “Nightly Rust”][how-rust-made-nightly] appendix
of the Book and the [Stability attributes][stability-attributes] section of the
Rustc Dev Guide for more details.

[how-rust-made-nightly]: https://doc.rust-lang.org/book/appendix-07-nightly-rust.html
[stability-attributes]: https://rustc-dev-guide.rust-lang.org/stability.html
Commit	Line	Data
94222f64 XL	1	Multiple stability attributes were declared on the same item.
	2
	3	Erroneous code example:
	4
	5	```compile_fail,E0544
	6	#![feature(staged_api)]
	7	#![stable(since = "1.0.0", feature = "rust1")]
	8
	9	#[stable(feature = "rust1", since = "1.0.0")]
	10	#[stable(feature = "test", since = "2.0.0")] // invalid
	11	fn foo() {}
	12	```
	13
	14	To fix this issue, ensure that each item has at most one stability attribute.
	15
	16	```
	17	#![feature(staged_api)]
	18	#![stable(since = "1.0.0", feature = "rust1")]
	19
	20	#[stable(feature = "test", since = "2.0.0")] // ok!
	21	fn foo() {}
	22	```
	23
	24	See the [How Rust is Made and “Nightly Rust”][how-rust-made-nightly] appendix
	25	of the Book and the [Stability attributes][stability-attributes] section of the
	26	Rustc Dev Guide for more details.
	27
	28	[how-rust-made-nightly]: https://doc.rust-lang.org/book/appendix-07-nightly-rust.html
	29	[stability-attributes]: https://rustc-dev-guide.rust-lang.org/stability.html