[Development] Dropping VS 2012 in Qt 5.7

[Thiago Macieira]

Just starting a new thread to get the attention of those that may have missed 
it in the other platform.

The proposal is to drop VS 2012 support in Qt 5.7 already, instead of 
supporting it in 5.7 only and dropping in 5.8.

The rationale is that we need VS2012 for WEC 2013 support, but there's no 
point in supporting that operating system in Qt 5.7. It suffices that it is 
supported in Qt 5.6, which is the long-term release. In other words, needing 
WEC 2013 customers are better served by staying in Qt 5.6 than upgrading to 
5.7.

Opinions? Objections?

I'd like to see this answered BEFORE we release 5.6 so we can add this 
interesting tidbit to the changelog. The 5.5.0 changelog said:

 - Qt 5.7 will begin requiring certain C++11 features in order to
   compile. The minimum compiler versions for that release will be:
   * Clang 3.2 (included in XCode 5.0)
   * GCC 4.7
   * Intel C++ Composer XE 2013 SP1 (compiler version 14.0)
   * Microsoft Visual Studio 2012 (compiler version 17.0)

Since that went out, we've already risen our minimum Clang required version to 
3.4.

> > > In summary Qt does not gain anything from pushing WEC2013 to 5.8:
> > > 
> > > - Potential Qt Customers are not stranded due to 5.6
> > > - WEC2013 in 5.8 doesn't really enable more projects
> > > - MS says it is dead and licenses are hard to come by
> > > - the currently visible project pipeline is rather dry on this
> > > platform
> > > 
> > > *But* our C++11 offering is yet longer chained.
> > 
> > So why are we bothering with VS2012 for Qt 5.7 then? Why wait until 5.8?
> > 
> > Let's drop it now.
> 
> That is fine for me as well. As Alex wrote, most important is that Qt 5.6
> LTS supports both WEC7 and WEC13 and that latest for Qt 5.8 we no longer
> have these to slow down adoption of C++11 and other planned changes.
-- 
Thiago Macieira - thiago.macieira (AT) intel.com
  Software Architect - Intel Open Source Technology Center