AC_HEADER_STAT # sys/stat.h
AC_HEADER_STDBOOL # stdbool.h
AC_HEADER_STDC # stdlib.h string.h (implied: errno.h limits.h stdio.h)
AC_HEADER_STAT # sys/stat.h
AC_HEADER_STDBOOL # stdbool.h
AC_HEADER_STDC # stdlib.h string.h (implied: errno.h limits.h stdio.h)