[Development] Raising minimum CMake version to 3.16 for Qt6

[Joerg Bornemann]

On 5/6/21 12:16 AM, Scott Bloom wrote:

> One thing to consider here.
> 
> Visual Studio is now shipping CMake, its also getting updated for patches of a given version of VS, and is not the same from VS 2019 or VS 2017
> 
> I know of a couple of teams that are using the VS version of CMake on windows to alleviate the need for another install/setup app

Good point.
VS 2017 shouldn't be a concern, see [1].

I think we can assume that CMake 3.16 is available for VS 2019 users, or 
that it is easily made available by updating VS.
Anecdotal evidence: my VS 2019 installation, which is screaming for an 
update (16.8.2 -> 16.9.4) already ships CMake 3.18.


Cheers,

Joerg

[1] https://doc.qt.io/qt-6/supported-platforms.html