don't be too perf-greedy

diff --git a/src/librustc_mir/interpret/memory.rs b/src/librustc_mir/interpret/memory.rs
index 982463740974a95b0a9e298364e07b53c53410d1..689a29cff6e9e465554829b05194cf14da53f332 100644 (file)
--- a/src/librustc_mir/interpret/memory.rs
+++ b/src/librustc_mir/interpret/memory.rs
@@ -158,7 +158,7 @@ pub fn reallocate(
         }
 
         // For simplicities' sake, we implement reallocate as "alloc, copy, dealloc".
-        // FIXME: Do something more efficient.
+        // This happens so rarely, the perf advantage is outweighed by the maintenance cost.
         let new_ptr = self.allocate(new_size, new_align, kind)?;
         self.copy(
             ptr.into(),