diff --git a/clang/lib/Headers/CMakeLists.txt b/clang/lib/Headers/CMakeLists.txt
index 038859a513eb8..1b96ac417bf70 100644
--- a/clang/lib/Headers/CMakeLists.txt
+++ b/clang/lib/Headers/CMakeLists.txt
@@ -24,6 +24,7 @@ set(core_files
   stdcountof.h
   stdckdint.h
   stddef.h
+  stddefer.h
   __stddef_header_macro.h
   __stddef_max_align_t.h
   __stddef_null.h