Re: CMake minimum version to support

From: Niall Douglas (s_sourceforge_at_[hidden])
Date: 2021-06-02 17:53:40

On 02/06/2021 17:32, Peter Dimov via Boost wrote:
> I suppose the time has come to have the discussion on
> the minimum CMake version we will support for building
> Boost. Currently that's set to 3.5, which kind of works, but
> is fairly inconvenient.
> 
> The interesting options are
> 
> - CMake 3.8: required for use of the compile features
>   cxx_std_11, cxx_std_14, cxx_std_17, etc. Also allows
>   source_group(TREE, which is used by Json and
>   PropertyTree.

Some observations:

- RHEL7 ships with cmake 3.9

- Ubuntu 18.04 LTS ships with cmake 3.10

- Ubuntu 16.04 LTS ships with cmake 3.5.

I can tell you that my users used to complain loudly if cmake 3.5 wasn't
supported, probably because of Ubuntu 16.04 LTS. A while back I bumped
my minimum cmake to 3.8, and users have not complained.

Me personally, I think cmake 3.8 or 3.9 is a good minimum, as it doesn't
needlessly inconvenience RHEL7 users. Speaking from personal experience,
everything added to cmake after 3.8 can be fairly easily worked around
or done without, whereas the lack of enough compile features flags is a
real pain.

Niall