Port #[rustc_dummy]

[mejrs]

r? @jdonszelmann

[rustbot]

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[rustbot]

Some changes occurred in compiler/rustc_passes/src/check_attr.rs

cc @jdonszelmann

Some changes occurred in compiler/rustc_attr_parsing

cc @jdonszelmann

Some changes occurred in compiler/rustc_attr_data_structures

cc @jdonszelmann

[jdonszelmann]

Needs a little bit of work. If you're using the attr in an invalid position it'll be checked twice now (take a look at the other prs how they solve this)

[jdonszelmann]

@rustbot author

[rustbot]

Reminder, once the PR becomes ready for a review, use @rustbot ready.

[GrigorenkoPV]

Needs a little bit of work. If you're using the attr in an invalid position it'll be checked twice now (take a look at the other prs how they solve this)

In compiler/rustc_parse/src/validate_attr.rs, in check_builtin_meta_item you need to add sym::rustc_dummy to the giant match pattern. I'm not aware if anything else is needed.

And, as a personal request, could you please add it not next to inline, may_dangle, rustc_pass_by_value, or repr — it would help with avoiding conflicts with #143402 & #143403.

[mejrs]

you need to add sym::rustc_dummy to the giant match pattern. I'm not aware if anything else is needed.

I don't, actually. That pattern is unreachable, because check_builtin_meta_item is never called for rustc_dummy.