[cmake-developers] A policy for Policies

[Brad King]

On 06/10/2015 03:52 PM, Domen Vrankar wrote:
> I've read it in Mastering CMake and had to search for it today...  On
> page 42 it says that by default if cmake_minimu_required is missing it
> sets policy version of 2.4.

That's because version 2.6 was the first to introduce policies so
using 2.4 leaves them all unset.  Prior to that we had another
mechanism called CMAKE_BACKWARDS_COMPATIBILITY which is now ignored
when the version requested is 2.6 or higher.  We cannot change the
default value without possibly breaking existing scripts.

-Brad