Odd "error[E0658]: is unstable" diagnostic

[jonas-schievink]

#[link(name = "c", cfg(yes))]
extern {}

error[E0658]: is unstable
 --> src/lib.rs:1:1
  |
1 | #[link(name = "c", cfg(yes))]
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  |
  = note: for more information, see https://github.com/rust-lang/rust/issues/37406

🤔

In addition to the malformed diagnostic, the tracking issue has been closed already. According to https://rust-lang.github.io/rfcs/1721-crt-static.html#lazy-link-attributes, this is supposed to be a permanently-unstable implementation detail. In that case, should the link be updated to point somewhere else?

This issue has been assigned to @Rustin-Liu via this comment.

[estebank]

The wording can be easily fixed at

rust/src/librustc_metadata/native_libs.rs

Line 165 in 699f83f

feature_err(&self.tcx.sess.parse_sess, sym::link_cfg, span.unwrap(), "is unstable")

.

The link can't be changed to a non-issue because of how the machinery is currently set up, but we can update the description of the ticket to point at RFC 1721.

[0xPoe]

@rustbot claim