-extern NORETURN(fatal(const char *message, ...));
-extern NORETURN(fatal_perror(const char *message, ...));
-extern NORETURN(fatal_status(int status, const char *message, ...));
-extern NORETURN(fatal_perror_status(int status, const char *message, ...));
+extern NORETURN(fatal(const char *message, ...)) FORMAT(printf,1,2);
+extern NORETURN(fatal_perror(const char *message, ...)) FORMAT(printf,1,2);
+extern NORETURN(fatal_status(int status, const char *message, ...))
+ FORMAT(printf,2,3);
+extern NORETURN(fatal_perror_status(int status, const char *message, ...))
+ FORMAT(printf,2,3);