Does buck2 support build trimming if no changes?

[AlexeyDmitriev]

Suppose target a depends on b which depends on c which builds file file. Suppose I changed the file, with only non meaningful changes (think added spaces in c++ file), and after recompilation c didn't change.

Does buck2 avoid building b and a?

I believe it's done in bazel but I haven't found this info on buck2 webiste

[cbarrete]

Yes, this is known as early cutoff. I don't think it's documented though.