diff --git a/evconfig-private.h.in b/evconfig-private.h.in
index 8d87927a..cffdf531 100644
--- a/evconfig-private.h.in
+++ b/evconfig-private.h.in
@@ -1,5 +1,7 @@
 /* evconfig-private.h template - see "Configuration Header Templates" */
 /* in AC manual.  Kevin Bowling <kevin.bowling@kev009.com */
+#ifndef _EVENT_EVCONFIG__PRIVATE_H
+#define _EVENT_EVCONFIG__PRIVATE_H
 
 /* Enable extensions on AIX 3, Interix.  */
 #ifndef _ALL_SOURCE
@@ -37,3 +39,5 @@
 #ifndef _POSIX_SOURCE
 #undef _POSIX_SOURCE
 #endif
+
+#endif