diff --git a/auto/os/darwin b/auto/os/darwin
index b4b3ad3..429468f 100644
--- a/auto/os/darwin
+++ b/auto/os/darwin
@@ -17,6 +17,9 @@
 MAIN_LINK=
 MODULE_LINK="-shared -Wl,-undefined,dynamic_lookup"
 
+CC_AUX_FLAGS="$CC_AUX_FLAGS -D__APPLE_USE_RFC_3542"
+
+
 # kqueue
 
 echo " + kqueue found"
@@ -86,7 +89,6 @@
 
 # sendfile()
 
-CC_AUX_FLAGS="$CC_AUX_FLAGS"
 ngx_feature="sendfile()"
 ngx_feature_name="NGX_HAVE_SENDFILE"
 ngx_feature_run=yes