CMake deprecation warning

[fatcerberus]

Just happened to notice CMake 3.9.1 spits out this warning when building Allegro:

CMake Deprecation Warning at CMakeLists.txt:23 (cmake_policy):
The OLD behavior for policy CMP0026 will be removed from a future version
of CMake.

The cmake-policies(7) manual explains that the OLD behaviors of all
policies are deprecated and that a policy should be set to OLD only under
specific short-term circumstances. Projects should be ported to the NEW
behavior and not rely on setting a policy to OLD.

[HerrBvomSee]

When I see it correctly, Allegro wants at least a 2.8.5 CMake
cmake_minimum_required(VERSION 2.8.5 FATAL_ERROR)
but the deprecation warning and corresponding new functionality was introduced in CMake 3.x

So should the minimal CMake of Allegro upgrade to 3.x?

[dos1]

Just for reference: https://cmake.org/cmake/help/v3.0/policy/CMP0026.html

It should be checked where and why Allegro reads the LOCATION property, and if necessary, it should be replaced with $<TARGET_FILE> generator expression. As far as I can see, this expression seems to be supported by CMake 2.8.5 as well, so there should be no need for raising the version requirement.