diff --git a/tools/analysis/trace-tools/src/lib/print.rs b/tools/analysis/trace-tools/src/lib/print.rs
index 3791bee3c8..bba9b34248 100644
--- a/tools/analysis/trace-tools/src/lib/print.rs
+++ b/tools/analysis/trace-tools/src/lib/print.rs
@@ -123,6 +123,8 @@ pub fn print_events<R: BorrowingRead + Send, W: Write + Send>(
 
             let env = BufferEnv::new(scratch, header, data);
 
+            // rustc fails to infer Higher Rank Trait Bound (HRTB) for the lifetime of references
+            // passed as parameters, so we force them to be
             fn ensure_hrtb<T1, T2, U, F>(f: F) -> F
                 where
                     F: FnMut(&mut T1, &T2) -> U