Skip single use lifetime lint for generated opaque types #88650
Conversation
As reported in issue rust-lang#77175, the opaque type generated by the desugaring process of an async function uses the lifetimes defined by the originating function. The definition ID for the lifetimes in the opaque method is different from the one in the originating async function and it could therefore be considered a single use of the lifetimne, this causes the single_use_lifetimes lint to fail compilation if explicitly denied. This fix skips the lint for lifetimes used only once in generated opaque types for an async function that are declared in the parent async function definition.
|
Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @wesleywiser (or someone else) soon. Please see the contribution instructions for more information. |
rust-highfive
added
the
S-waiting-on-review
|
This is a copy of the original #78004 PR. The CR comments on using an |
|
@bors try @rust-timer queue Noticed that we're fetching the item unconditionally on every DefId to see if it might be an async fn. Running a perf check to see if it has performance implications. |
|
Awaiting bors try build completion. @rustbot label: +S-waiting-on-perf |
rustbot
added
the
S-waiting-on-perf
|
⌛ Trying commit 0696c28 with merge 5d2576145eba4a6649c0c2b27d4a774b8138797b... |
|
☀️ Try build successful - checks-actions |
|
Queued 5d2576145eba4a6649c0c2b27d4a774b8138797b with parent f7c00dc, future comparison URL. |
|
Finished benchmarking try commit (5d2576145eba4a6649c0c2b27d4a774b8138797b): comparison url. Summary: This benchmark run did not return any relevant changes. If you disagree with this performance assessment, please file an issue in rust-lang/rustc-perf. Benchmarking this pull request likely means that it is perf-sensitive, so we're automatically marking it as not fit for rolling up. @bors rollup=never |
rustbot
removed
the
S-waiting-on-perf
apiraino
added
the
T-compiler
|
Anything else we need to do here @estebank? |
|
@bors r+ |
|
📌 Commit 0696c28 has been approved by |
bors
added
S-waiting-on-bors
|
☀️ Test successful - checks-actions |
|
Finished benchmarking commit (23afad6): comparison url. Summary: This benchmark run did not return any relevant changes. If you disagree with this performance assessment, please file an issue in rust-lang/rustc-perf. @rustbot label: -perf-regression |
Fix: #77175
The opaque type generated by the desugaring process of an async function uses the lifetimes defined by the originating function. The DefId for the lifetimes in the opaque type are different from the ones in the originating async function - as they should be, as far as I understand, and could therefore be considered a single use lifetimes, this causes the single_use_lifetimes lint to fail compilation if explicitly denied. This fix skips the lint for lifetimes used only once in generated opaque types for an async function that are declared in the parent async function definition.
More info in the comments on the original issue: 1 and 2