diff --git a/ext/tk/tcltklib.c b/ext/tk/tcltklib.c
index 0798d0b24d..2d45f7511b 100644
--- a/ext/tk/tcltklib.c
+++ b/ext/tk/tcltklib.c
@@ -20,11 +20,7 @@
 #endif
 
 #undef RUBY_UNTYPED_DATA_WARNING
-#ifdef HAVE_BUILTIN___BUILTIN_CHOOSE_EXPR_CONSTANT_P
-#define RUBY_UNTYPED_DATA_WARNING 1
-#else
 #define RUBY_UNTYPED_DATA_WARNING 0
-#endif
 
 #ifdef HAVE_RB_THREAD_CHECK_TRAP_PENDING
 static int rb_thread_critical; /* dummy */