utypes.c:16: Include file <sys/types.h> matches the name of a POSIX library,
    but the POSIX library is not being used.  Consider using +posixlib or
    +posixstrictlib to select the POSIX library, or -warnposix to suppress this
    message.
utypes.c:3:23: Variable uchar inconsistently redeclared as datatype
   utypes.c:13: Previous definition of uchar as variable: ?
utypes.c:4:24: Variable ushort inconsistently redeclared as datatype
   utypes.c:15: Previous definition of ushort as variable: ?
utypes.c:5:22: Variable uint inconsistently redeclared as datatype
   utypes.c:14: Previous definition of uint as variable: ?
utypes.c:6:23: Variable ulong inconsistently redeclared as datatype
   utypes.c:16: Previous definition of ulong as variable: ?
utypes.c: (in function f)
utypes.c:26:8: Variable src_bytes declared but not used

Finished checking --- 6 code warnings, as expected