Qt 5.6 LTS vs. 5.7 - should MacPorts provide both and how?

[René J.V. Bertin]

On Saturday September 03 2016 11:53:04 Ryan Schmidt wrote:

>In this hypothetical scenario, yes, that's true. I have no knowledge of what those features might be 

That should be easier to answer than the other questions raised: each Qt release always comes with a description of the new features introduced with that release.

>or how detrimental omitting them might be.

That can only be answered on a case-by-case basis. KF5 for instance has seen a rather drastic increase of the minimum required Qt version because certain of the KF5 frameworks use Qt features in core functionality (where core is of course "what they call core"). It wouldn't have been impossible to check for those availability of those Qt features, but that would have made the code more complex (too complex apparently, in "their" opinion), and AFAIK this is only feasible at build time.

In short, dependent code may have a limited feature set when built against an earlier-than-preferred Qt version, or else it may simply refuse to build.

I've started asking around on a couple of lists where I might get some actual answer to what extent we might want to consider supporting the 2 versions.

R.