possible to adjust OPTIONS_DEFAULT based on COMPILER_TYPE?

[Mathieu Arnold]

+--On 10 mars 2015 16:30:35 -0700 Don Lewis <truckman at FreeBSD.org> wrote:
| I've run into a situation where I'd like to change OPTIONS_DEFAULT based
| on the value of the value of COMPILER_TYPE.  I'm setting USE_GCC=yes. If
| the base compiler is gcc, then I can enable a particular option to make
| the port more featureful.  If the base compiler is clang, then some of
| the other ports the option depends on are C++ code that gets compiled
| with clang and the port breaks because of the libstdc++ vs. libc++
| conflict.  In that case, I'd like to disable the option to at least have
| working binary packages available, even though they aren't as
| featureful.
| 
| This doesn't look possible, though.  OPTIONS_DEFAULT needs to be set
| before the .include <bsd.port.options.mk>, and COMPILER_TYPE isn't set
| until after that, or possibly even after bsd.port.pre.mk.

Mmmm, yes, you're kinda stuck, I've already had a look, and it's not
possible to have options working including port.options and also be able to
change stuff after it.

Though, USE_GCC=yes will never use the old base gcc, but always lang/gcc
(well, the one defined in bsd.default-versions, which if left alone is
lang/gcc), USE_GCC=any will use gcc from base though, but I'm not sure you
can have a good reason to use it.

-- 
Mathieu Arnold