mod-localtime
%Y
2020
%Y
gmtime == gmtime
mod-localtime-indirect:
make: Invalid time value: ${:U1593536400}}

ocaltime=1593536400}
parse-errors:
make: Invalid time value: -1}.

: -1 becomes ocaltime=-1}.
make: Invalid time value:  1}.

: space 1 becomes ocaltime= 1}.
: 0 becomes ok.
: 1 becomes Thu Jan  1 01:00:01 1970.
: INT32_MAX becomes Tue Jan 19 04:14:07 2038.
: INT32_MAX + 1 becomes Tue Jan 19 04:14:08 2038.
make: Invalid time value: 10000000000000000000000000000000}.

: overflow becomes ocaltime=10000000000000000000000000000000}.
make: Invalid time value: error}.

: letter becomes ocaltime=error}.
exit status 0