Issue: #include <stdio.h> shall not cause intmax_t to be defined

Hi all,

Issue: #include <stdio.h> shall not cause intmax_t to be defined. However,
now it causes. This is because now <stdio.h> includes <sys/types.h>, which
includes <sys/_stdint.h>.
Note: per C11 the types intmax_t and uintmax_t defined in the header
<stdint.h>, and <stdint.h> is not included in <stdio.h>.
Consider fixing.

--
Pavel