Buildworld and not clean anything of a previous time

[MG]

Use the existing completed results in /usr/obj.
What's the official way in FreeBSD 15 without using connfiguration files and only command parameters?

NO_CLEAN=1
WITHOUT_CLEAN=1
-DNOCLEAN
Other options involve changing make.conf or src.conf...

 

[SirDice]

What's the official way in FreeBSD 15

As far as anything "official", NO_CLEAN (or any of the variations) certainly isn't recommended to do, it has a few caveats you need to be aware of. And they will bite you at some point.

A better solution, albeit not perfect, is WITH_META_MODE. It's definitely safer to do.

MetaMode - FreeBSD Wiki

Though it says to put it in /etc/src-env.conf, it works just as fine from the command line; make -DWITH_META_MODE {...}

 

[MG]

It won't bite me. Doing this for years. The system build compiler variables have never been consistent in my opinion.
What command do I need when I copied the entire /usr/obj to another clean system tree?
(This might sound overcomplicated but it's my phased 1-man custom release project. Need to keep track of things and not waste time on compiing the same all the time. Everything works already but I lost the not clean requirements. Is it me or 14>15?)