Index: exec/crypto.c
===================================================================
--- exec/crypto.c	(revision 1766)
+++ exec/crypto.c	(working copy)
@@ -37,8 +37,8 @@
 #define ENDIAN_LITTLE
 #elif _BYTE_ORDER == _BIG_ENDIAN
 #define ENDIAN_BIG
-#elif
-#warning "cannot detect byte order"
+#else
+#error "cannot detect byte order"
 #endif
 
 #if defined(COROSYNC_LINUX)