diff --git a/clang/include/clang/Analysis/FlowSensitive/CachedConstAccessorsLattice.h b/clang/include/clang/Analysis/FlowSensitive/CachedConstAccessorsLattice.h
index 78b03d325efd9..257f96a3a4bc8 100644
--- a/clang/include/clang/Analysis/FlowSensitive/CachedConstAccessorsLattice.h
+++ b/clang/include/clang/Analysis/FlowSensitive/CachedConstAccessorsLattice.h
@@ -121,6 +121,7 @@ joinConstMethodMap(
                               llvm::SmallDenseMap<const FunctionDecl *, T *>>
         &Map2,
     LatticeEffect &Effect) {
+  // Intersect the two maps, and note if change was made.
   llvm::SmallDenseMap<const RecordStorageLocation *,
                       llvm::SmallDenseMap<const FunctionDecl *, T *>>
       Result;