[Interest] Qt Versioning Questions

[Kai Koehne]

> -----Original Message-----
> From: Interest [mailto:interest-bounces+kai.koehne=qt.io at qt-project.org]
> On Behalf Of Jason H
> Sent: Wednesday, September 14, 2016 4:53 PM
> To: Interests Qt <interest at qt-project.org>
> Subject: [Interest] Qt Versioning Questions
> 
> So Qt has 3 codelines being maintained (AFAIK): 5.6 (LTS), 5.7, 5.8
> 
> I need fixes that are in 5.6.2. First question: When will those fixes from 5.6.2
> be available in 5.7 and 5.8? Given the timing it looks like 5.6.2->5.7.1-5.8?

This is correct.

> Also I am waiting for https://bugreports.qt.io/browse/QTBUG-51133 to land
> in some version which will be my next used Qt version after 5.6.2. The
> change for 51133 is exposing "scaledFontSize" in the QML Text element. I
> understand this is an "API" change and can only be delivered in 5.8, though I
> don't think it would break binary compatibility? Is that correct?

Binary compatibility is indeed less of a concern, since this is for a QML element.
However, new properties should only appear in a new import, because otherwise
bindings for existing applications might change unexpectedly. Introducing new
properties in a patch level release would also break the promise that an app 
compiled against 5.6.2 can still run with 5.6.0. To cite the ChangeLog for 5.6.1:

  Qt 5.6.1 is a bug-fix release. It maintains both forward and backward
  compatibility (source and binary) with Qt 5.6.0.

> I also
> understand that 5.8 is approaching freeze, so will this land in 5.8 or will I have
> to wait another year to see it in 5.9? Given the amount of awesome going
> into 5.8, I'd like to see it there as I don't have anything in 5.7 of interest and
> I'd not like to wait a year to get this (I'd actually love to see it arrive in the 5.6
> line)

5.8 is already in feature freeze, so I'm afraid this has to wait for 5.9. But 5.9 will 
hopefully not take a year, current plan says April 2017. 

Regards

Kai