[cmake-developers] c++ feature detection and usage requirements

[Brad King]

On 08/29/2013 11:14 AM, Stephen Kelly wrote:
> Another option would be not to have the VERSION in the signature, but always 
> use CMAKE_MINIMUM_VERSION_REQUIRED to determine what to generate. 
> 
> The content generated depends only on the features of the cmake binary being 
> run, so it relieves users of the need to additionally maintain the VERSION 
> here and figure out how that maps to their minimum cmake version.

A project may wish to update to a newer required CMake version for some
other feature but is not ready to port their header generation.  We
could define the versions w.r.t. the CMake version and make VERSION
optional.  If not present use CMAKE_MINIMUM_VERSION_REQUIRED.  If
present then fail if VERSION is newer than CMAKE_MINIMUM_VERSION_REQUIRED.

We also need a plan to phase out support for ancient versions in the
future.

-Brad