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diff --git a/src/librustc_mir/monomorphize/collector.rs b/src/librustc_mir/monomorphize/collector.rs
index e85e842031dbb0ede4b7ad70edd25213048134ec..511a5fbc617951e94343a1cb6bc5ac8ba4cfab77 100644 (file)
--- a/src/librustc_mir/monomorphize/collector.rs
+++ b/src/librustc_mir/monomorphize/collector.rs
@@ -398,6 +398,9 @@ fn record_accesses<'tcx>(
         mono_item.instantiation_mode(tcx) == InstantiationMode::LocalCopy
     };
 
+    // We collect this into a `SmallVec` to avoid calling `is_inlining_candidate` in the lock.
+    // FIXME: Call `is_inlining_candidate` when pushing to `neighbors` in `collect_items_rec`
+    // instead to avoid creating this `SmallVec`.
     let accesses: SmallVec<[_; 128]> = callees
         .into_iter()
         .map(|mono_item| (*mono_item, is_inlining_candidate(mono_item)))