diff --git a/llvm/include/llvm/CodeGen/GlobalISel/GISelChangeObserver.h b/llvm/include/llvm/CodeGen/GlobalISel/GISelChangeObserver.h
index b4aa2e510eee..a2876b621279 100644
--- a/llvm/include/llvm/CodeGen/GlobalISel/GISelChangeObserver.h
+++ b/llvm/include/llvm/CodeGen/GlobalISel/GISelChangeObserver.h
@@ -1,4 +1,4 @@
-//===----- llvm/CodeGen/GlobalISel/GISelChangeObserver.h ------------------===//
+//===----- llvm/CodeGen/GlobalISel/GISelChangeObserver.h --------*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.