[build2] LTO and parallelization with build2

[Matthew Krupcale]

On Tue, Aug 11, 2020 at 8:53 AM Boris Kolpackov <boris at codesynthesis.com> wrote:
>
> Thanks, I've reviewed the changes and pushed my tweaks:
>
> https://git.build2.org/cgit/build2/log/?h=lto-parallelization
>
> It's mostly cosmetic though there were a few issues (especially
> in the Clang part). Could you review them and if happy, I will
> merge everything to master.

Yep, everything looks good.

> Note also that I moved the option translation after the low-
> verbosity diagnostics. The thinking being that in the -v
> output it is more useful to see -flto=auto rather than some
> fixed number (e.g., in case the user wants to re-run the
> command manually).

Yeah, makes sense.