On Friday 22 Jan 2016 21:04:48 Nikos Chantziaras wrote:
> I have a weird problem. I have an ebuild where either qt4 or qt5 can be
> enabled. They are both disabled by default and I have to choose which
> one I want. The ebuild does that with:
> 
>    IUSE="qt4 qt5"
>    REQUIRED_USE="^^ ( qt4 qt5 )"
> 
> I'm on the plasma profile which enabled qt5 automatically. However,
> portage complains:
> 
>    The following REQUIRED_USE flag constraints are unsatisfied:
>    exactly-one-of ( qt4 qt5 )
> 
> The qt4 USE flag is enabled. I can't see where. I didn't enable it
> anywhere in any of my /etc/portage/* files. If I emerge with:
> 
>    USE="-qt4" emerge package
> 
> then it works. So I have to explicitly disable the qt4 USE flag even
> though I didn't enable it in the first place.
> 
> Can someone enlighten me?

euse -I qt4

should provide some pointers.  It may be your desktop profile?

-- 
Regards,
Mick