add support for appleclang and update cmake

[gold-development]

Added support for AppleClang and update cmake version

[silviucpp]

Mac os build seems broken . any plan to commit this ?

[absurdfarce]

Apologies, I've been distracted by too many things. @yifan-c can you take a look at this one as well?

[absurdfarce]

A few questions but I'll defer to @yifan-c on the details since I know he's been working much more directly in this space.

[absurdfarce]

Can you elaborate on a couple things here?

First: why is it necessary to change the cmake minimum version at all in order to fix this?

Second: if it is necessary to change it why are we tweaking it only in three CMakeLists files rather than uniformly throughout the project?

[toptobes]

Looking at the git logs, I'm fairly certain what happened is that they were originally basing this off the version of the c++ driver 2 weeks before this PR was created, when it was still using cmake version 2.8.12 (so this was intended as an upgrade, not a downgrade)

See:

❯ git lg                               
* a22a11a3 golddevelopment - (HEAD -> gold-development/trunk) add support for appleclang and update cmake (5 months ago)
* e5a486ac Sigmanificient - Bump minimum required version for cmake4 compatibility (5 months ago)

❯ git lg -L 1,1:CMakeLists.txt                    
* a22a11a3 golddevelopment - (HEAD -> gold-development/trunk) add support for appleclang and update cmake (5 months ago)| 
| diff --git a/CMakeLists.txt b/CMakeLists.txt
| --- a/CMakeLists.txt
| +++ b/CMakeLists.txt
| @@ -1,1 +1,1 @@
| -cmake_minimum_required(VERSION 3.10)
| +cmake_minimum_required(VERSION 3.5)

* e5a486ac Sigmanificient - Bump minimum required version for cmake4 compatibility (5 months ago)| 
| diff --git a/CMakeLists.txt b/CMakeLists.txt
| --- a/CMakeLists.txt
| +++ b/CMakeLists.txt
| @@ -1,1 +1,1 @@
| -cmake_minimum_required(VERSION 2.8.12)
| +cmake_minimum_required(VERSION 3.10)

P.S. AppleClang only got differentiated from Clang in 3.0 which is why this wasn't an issue previously

[absurdfarce]

This seems reasonable @toptobes but even if it is the case I'd still argue for a uniform cmake requirement throughout the project. Note the commit referenced above; in that case we updated cmake_minimum_required() throughout the project. If we're going to change the cmake requirement at all here it seems like we should do the same.

[toptobes]

➕

[absurdfarce]

I'll let him speak on this for sure but I believe @yifan-c was able to get this working more generally using regex matching:

if("${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang$" 

That's probably more desirable as it covers a broader range of clang derivatives. cmake supports a number of such variants so as long as the flags in question apply to clang generally (i.e. isn't some custom flag implemented for a specific clang variant) the more general syntax seems preferrable.

[absurdfarce]

@gold-development Are you able to speak to any of the comments on this PR? I'd love to get this change into 2.17.2 but I do think we have a few points to talk about in the changes above.