[LLVMdev] [RFC] Raising minimum required Visual Studio version to 2013 for trunk

[Aaron Ballman]

On Thu, Aug 21, 2014 at 9:02 PM, Chandler Carruth <chandlerc at google.com> wrote:
>
> On Thu, Aug 21, 2014 at 4:48 PM, Aaron Ballman <aaron at aaronballman.com>
> wrote:
>>
>> On Thu, Aug 21, 2014 at 7:35 PM, Chris Bieneman <beanz at apple.com> wrote:
>> > This thread hasn’t had too much traffic, but it sounds like many people
>> > are
>> > in favor and there is no strong opposition. If I understand Aaron’s only
>> > objection was based on preserving existing policy rather than a
>> > technical
>> > reason.
>> >
>> > Anyone want to make the official call?
>>
>> I am still opposed.
>>
>> We told the community less than nine months ago (when we made the
>> C++11 switch) that we would support the last two versions of MSVC. Now
>> we're saying "only the latest version, because it has nice things."
>> That would make sense if those nice things were something we couldn't
>> live without, or if there was a long delay for a new release of MSVC.
>> Neither of those things seem to be the case, so I'm not certain why we
>> would change our developer policy on three day's notice.
>
>
> So:
>
> 1) When we had the discussion 9 months ago I specifically called out that
> MSVC might be reasonable rev faster than other compilers due to the rapidly
> improving feature set. I think that this thread is essentially exploring the
> possibility of actually doing that.
>
> 2) I actually think the features listed are *very* valuable. If we can move
> faster, I think we should. But there is an "if we can" in there.
>
> 3) I completely agree about the 3-days thing. This is a good start, and none
> have really shouted in objection. That's a good sign, but I would wait at
> least until next week so that we have an LLVM weekly post, and digests etc
> go out so that you reach an even larger audience. You should also email
> cfe-dev and lldb-dev because those projects are very impacted by this
> change.
>
> If next week, no one has raised an objection of the form "this would break
> my usage of LLVM" or "I can't easily upgrade for N months", then I think we
> should move forward. At that point I think you should commit something to
> the CMake build which errors on old versions of MSVC *without* updating
> documentation, policy or code. You'll probably have tto revert it and get
> some bots updated. Once the build bot fallout is fixed, and that commit
> stays in tree for roughly a week without shouting, I think we can update the
> documentation.

That sounds like a reasonable plan to me, thanks!

~Aaron