Re: PKG_DEFAULT_OPTIONS

[Robert Elz <kre%munnari.OZ.AU@localhost>]

    Date:        Mon, 2 May 2016 10:50:25 +0200
    From:        Thomas Klausner <wiz%NetBSD.org@localhost>
    Message-ID:  <20160502085025.GA6373%danbala.tuwien.ac.at@localhost>

  | That includes gnutls/bl3.mk if ucommon was built with the gnutls
  | option.

Actually, it doesn't - it includes it if a build of ucommon made now
would use the gnutls option, it tells nothing at all about the state of
the universe when ucommon was last actually built.

I know one of my fairly common practices is to notice when building a
package that I forgot an option I would have preferred on, but rather
than going back and changing things, and rebuilding, I just say "oh well,
next time" - but I also know my memory is crap, so rather than assuming
I will remember next time, I change /etc/mk.conf now to include the option
ready for next time, whenever that happens.

In that situation, if some package that depended upon the one whose options
have no changed is to be built, and it used the method suggested to discover
how it should be built, it will use incorrect options, and fail.

The only solutions to this would be to forbig changing mk.conf anytime
after the first package is built, until everything is removed and we start
again (and that is just no practical) or to actually query the package
database, and see what options the package we depend upon was actually
built with.

lre