[llvm-dev] [cfe-dev] Fwd: Raising CMake minimum version to 3.4.3

[Renato Golin via llvm-dev]

On 27 April 2016 at 15:39, Rafael Espíndola <rafael.espindola at gmail.com> wrote:
> Yes. It is a move to put linux developers in the same position as
> windows and OS X ones, which is a *very* reasonable thing to do.

Apart from the fact that neither Windows nor OSX users have a choice.

We have discussed this before, Rafael, and I don't think doing it
again will yield different results unless new evidence is brought to
light.

Unless there is a feature in a newer CMake that we *must* have, I see
no need to upgrade the version. In the same way we've been holding on
C++11/14 functionality because MSVC couldn't cope with anything until
recently.

Trying to go too fast on the cool tools can create a patchwork of
versions and functionality that will make it very hard to debug
buildbot problems.

LLVM is not a toy any more, we can't just expect that everyone can get
the same environment we have on our own machines, or we'll fall into
the "works for me" style of closing bugs that is pervasive of open
source projects where only a few people ever commit code to.

Now, back to Chris' point:

Is the ExternalProject the only sane way to build compiler-rt and
libc++? Because this IS a big point.

Will it allow a way to build Compiler-RT and libc++ for *all*
supported platforms (as in -DLLVM_TARGETS_TO_BUILD)? Would it be
possible (even if not nice) to do so with an older version of CMake?
How worse would it be, if possible?

Until we can answer all these questions, build times and personal
preferences have no impact on such a big decision.

cheers,
--renato