diff --git a/src/OptionHandlerFactory.cc b/src/OptionHandlerFactory.cc
index 2e1cf118..f8b99b5f 100644
--- a/src/OptionHandlerFactory.cc
+++ b/src/OptionHandlerFactory.cc
@@ -216,7 +216,6 @@ OptionHandlers OptionHandlerFactory::createOptionHandlers()
     handlers.push_back(op);
   }
 #endif // ENABLE_ASYNC_DNS
-#ifdef ENABLE_DIRECT_IO
   {
     // TODO Deprecated
     SharedHandle<OptionHandler> op
@@ -230,7 +229,6 @@ OptionHandlers OptionHandlerFactory::createOptionHandlers()
     op->addTag(TAG_FILE);
     handlers.push_back(op);
   }
-#endif // ENABLE_DIRECT_IO
   {
     SharedHandle<OptionHandler> op(new BooleanOptionHandler
                                    (PREF_ENABLE_RPC,
diff --git a/src/a2io.h b/src/a2io.h
index 3b065bc9..8b50f02b 100644
--- a/src/a2io.h
+++ b/src/a2io.h
@@ -137,10 +137,6 @@
 # define a2mkdir(path, openMode) mkdir(path, openMode)
 #endif // !__MINGW32__
 
-#if defined HAVE_POSIX_MEMALIGN && defined O_DIRECT
-# define ENABLE_DIRECT_IO 1
-#endif // HAVE_POSIX_MEMALIGN && O_DIRECT
-
 #define OPEN_MODE S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH
 #define DIR_OPEN_MODE S_IRWXU|S_IRWXG|S_IRWXO