From 751f3ce8e1c8bffe86b850e44bf0d08d47d10a77 Mon Sep 17 00:00:00 2001 From: Josh Triplett Date: Tue, 15 Jul 2025 20:09:04 -0700 Subject: [PATCH 1/2] Note the nightly version of Rust/Cargo needed --- content/inside-rust/call-for-testing-hint-mostly-unused.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/content/inside-rust/call-for-testing-hint-mostly-unused.md b/content/inside-rust/call-for-testing-hint-mostly-unused.md index 1830287e3..6e0cefebb 100644 --- a/content/inside-rust/call-for-testing-hint-mostly-unused.md +++ b/content/inside-rust/call-for-testing-hint-mostly-unused.md @@ -151,7 +151,7 @@ allow the top-level crate to override. ## How do I help? -We'd love for you to test out this feature on the latest Rust nightly compiler[^nightly]. +We'd love for you to test out this feature on the latest nightly Rust and Cargo (2025-07-16 or newer)[^nightly]. [^nightly]: Make sure to run `rustup update nightly` (or however you manage your Rust releases). From d2ae6e6bdad9561bf3eceff8a7a8324f943f25f9 Mon Sep 17 00:00:00 2001 From: Josh Triplett Date: Wed, 16 Jul 2025 10:50:05 -0700 Subject: [PATCH 2/2] Add caveat to discourage setting in RUSTFLAGS --- content/inside-rust/call-for-testing-hint-mostly-unused.md | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/content/inside-rust/call-for-testing-hint-mostly-unused.md b/content/inside-rust/call-for-testing-hint-mostly-unused.md index 6e0cefebb..9eb29dedc 100644 --- a/content/inside-rust/call-for-testing-hint-mostly-unused.md +++ b/content/inside-rust/call-for-testing-hint-mostly-unused.md @@ -45,7 +45,12 @@ possible. Applying this option to key crates you depend on (and use only a small subset of) can provide a substantial reduction in compile time, for debug builds and -especially for release builds. +especially for release builds. The remainder of this post shows how to apply +this option selectively using Cargo, when to use it, and how it performs. + +(Note that this option should *not* be applied to all crates, e.g. using +`RUSTFLAGS`. See the rest of this post for guidance on when to apply it, and +why it shouldn't be applied across the board.) ## How does this perform?