[LLVMdev] [RFC] Raise minimum required CMake version to 3.0

[Mehdi Amini]

Hi Tobias,

> On Feb 24, 2015, at 9:32 AM, Tobias Grosser <tobias at grosser.es> wrote:
> 
> On 24.02.2015 17:45, Tobias Grosser wrote:
>> On 09.02.2015 20:12, Chris Bieneman wrote:
>>> It came up on another thread that our current minimum required CMake
>>> version 2.8.8, has some bugs that cause issues when building with MSVC
>>> + Ninja, and one potential solution was to raise the minimum required
>>> version of CMake.
>>> 
>>> CMake 3.0 is now 6 months old and CMake 3.1 has been released. I would
>>> like to propose moving our minimum required CMake version to 3.0.
>>> 
>>> I’ve attached patches to enforce the change in case anyone wants to
>>> test it out.
>>> 
>>> Thoughts/comments/concerns/objections?
>> 
>> Hi Chris,
>> 
>> this update broke my cmake LLVM+Polly buildbot (to my knowledge most
>> other bots use autoconf). I reverted this temporarily to avoid the
>> buildbot noise (this comes a little late, as I was traveling the last
>> days).
>> 
>> The buildbot is based on the latest debian stable (wheezy), which comes
>> with cmake 2.8.9. Is 2.8.9 enough to fix the bug?
>> 
>> Also, could we just limit the cmake version on windows builds? In the
>> end on linux cmake 2.8.9 works great.
> 
> Rafael asked if updating the bot is not an option. It indeed is an option, but requires cmake to be manually downloaded and installed instead of using the available packages.
> 
> This is OK for one bot, but it will add complications for everybody who uses debian and wants to install LLVM. It also will make it more complicated to move to a fully cmake based build as all such debian based buildbots would require a manual installation of cmake (I have 12 more of these).
> 
> Before doing so I wanted to understand if it is indeed intended to require debian-stable users to *manually* install and manage cmake or if there is not a lower overhead version. Can this bug not be fixed for windows without complicating live for debian users?

In light of the list of new features that Chris listed, and considering that Debian 8 is frozen (RC1 already shipped in January) and should be released before the next LLVM version (but who knows with Debian…), do you have a plan to update CMake on all your bots? Or do you still have strong other concerns?

Thanks,

Mehdi