diff --git a/opal/util/output.h b/opal/util/output.h
index 4cb53ae8b9..46dddb9c0c 100644
--- a/opal/util/output.h
+++ b/opal/util/output.h
@@ -64,7 +64,12 @@
 
 #include "opal_config.h"
 
+#ifdef HAVE_STDARG_H
 #include <stdarg.h>
+#endif
+#ifdef HAVE_STDBOOL_H
+#include <stdbool.h>
+#endif
 
 #include "opal/class/opal_object.h"