Qt 5.6LTS vs 5.7+

[René J.V. Bertin]

On Saturday September 03 2016 21:06:17 Duncan wrote:

> Given the newness of that code in qt as well, I'd guess the wayland 
> support, directly or indirectly, is a big part of why they're requiring 
> qt-5.7 for various plasma components. 

Seems like it would have been more elegant to couple requirement of Qt 5.7 to a more advanced Wayland support, or something along those lines. I think I would in fact be quite happy if Wayland support were optional because I don't see myself using it anytime (not so) soon.

> I'm no qt expert, but I wouldn't 
> be surprised if that's one reason why 5.6 was chosen as an LTS as well -- 
> they can continue there with the immature wayland code and/or possibly 
> remove it and tell people to upgrade to 5.7+ for wayland, while 5.7 

That seems like it doesn't really fit with Qt's principle of backwards API and ABI compatibility, and the design based on platform architecture plugins (QPA). Code built and linked against Qt 5.6 is supposed to run with Qt 5.7 (as long as it doesn't use private APIs).
Your argument would make more sense if the evolving Wayland support interfered with support for the other QPAs. But it shouldn't; if you don't use Wayland you shouldn't be affected by changes in Wayland support at all.

R.