crossbuild: Make the CHECK_TIME variable work on Linux

[arichardson]

Summary

Linux /usr/bin/find doesn't understand the -mtime -0s flag.
Instead create a temporary file and compare that file's mtime to
sys/sys/param.h to check whether the clock is correct.

[imp]

Makefile

360 ↗

(On Diff #38756)

This is now wrong. This changes from 0s to 0 days. Due to funky roundings, this tests to see if the sys/sys/param.h file is one day or less old (or in the future), whereas on FreeBSD it tests if it is 1 second old or in the future. The difference is important and will lead to false positives.

"touch /tmp/junk && find ${.CURDIR}/sys/sys/param.h -newer /tmp/junk && rm /tmp/junk" would do the same thing and be portable...

[arichardson]

Use a temporary file instead

[imp]

Makefile

355 ↗

(On Diff #38884)

Thanks!