diff --git a/ChangeLog b/ChangeLog
index 8eeefbd34e..601d1ffb32 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Fri Sep 16 19:46:05 2016  NAKAMURA Usaku  <usa@ruby-lang.org>
+
+	* win32/Makefile.sub (config.h): fixed compile error with VC introduced
+	  by previous commit.
+
 Fri Sep 16 14:54:34 2016  URABE Shyouhei  <shyouhei@ruby-lang.org>
 
 	* internal.h (WARN_UNUSED_RESULT): moved to configure.in, to
diff --git a/win32/Makefile.sub b/win32/Makefile.sub
index e3fae91c65..dc198f63d2 100644
--- a/win32/Makefile.sub
+++ b/win32/Makefile.sub
@@ -604,6 +604,8 @@ $(CONFIG_H): $(MKFILES) $(srcdir)/win32/Makefile.sub $(win_srcdir)/Makefile.sub
 #define NOINLINE(x) __declspec(noinline) x
 !endif
 #define ALWAYS_INLINE(x) __forceinline x
+#define WARN_UNUSED_RESULT(x) x
+#define MAYBE_UNUSED(x) x
 #define UNREACHABLE __assume(0)
 #define ASSUME(x) __assume(!!(x))
 #define FUNC_STDCALL(x) __stdcall x