`windows-sys` v0.59.0 (latest version) hits a FCW on the latest nightly

[tgross35]

I happened to notice this on the playground https://play.rust-lang.org/?version=nightly&mode=debug&edition=2024&gist=ef32dafd88af58c9b698a698fd39d818:

warning: the following packages contain code that will be rejected by a future version of Rust: windows-sys v0.59.0

It appears on nightly but not beta so this must be from a recent change. I don't currently have access to a Windows machine to check out what the error actually is, but considering windows-sys is a top 100 crate, we should probably consider removing the relevant lint from report_in_deps before the beta branch to give some migration time. Otherwise almost everybody developing on Windows is going to have a new error that they can't do much about.

[tgross35]

Cc @kennykerr since I believe you maintain windows-sys

[workingjubilee]

Probably code involving extern "stdcall", cc @RalfJung

[tgross35]

That makes perfect sense, #141435 includes

rust/compiler/rustc_lint_defs/src/builtin.rs

Line 3667 in 1c04750

report_in_deps: true,

. Maybe we could drop the report_in_deps for a version or two so windows-sys has a chance to migrate?

[tgross35]

Linking Zulip discussion https://rust-lang.zulipchat.com/#narrow/stream/122651-general/topic/windows-sys.20FCW

[workingjubilee]

I am revising my guess: it actually is probably usages of extern "cdecl".

[Noratrieb]

I agree that emitting an FCW on every windows build is really bad, we should back that out again. I can do that but will only get to it later today, so if someone else wants to do it that'd be great.