--- Libc/Libc-1669.40.2/include/fmtmsg.h
+++ Libc/Libc-1698.100.8/include/fmtmsg.h
@@ -28,6 +28,10 @@
 
 #ifndef _FMTMSG_H_
 #define	_FMTMSG_H_
+
+#include <_bounds.h>
+
+_LIBC_SINGLE_BY_DEFAULT()
 
 /* Source of condition is... */
 #define	MM_HARD		0x0001	/* ...hardware. */