llvm dev - Aug 2016 - [cfe-dev] Revisiting our informal policy to support two versions of MSVC

Hi,

This sounds like a decent idea to me. However we use 2013 for all our
windows builds at the moment and it will take around 2 weeks to upgrade the
installations on our cluster. We're pushing this hard to get it done soon
so we don't get caught short, but a grace period would be much appreciated.

Cheers,

James

On Tue, 2 Aug 2016 at 21:24 Nico Weber via cfe-dev <cfe-dev at
lists.llvm.org>
wrote:
> On Tue, Aug 2, 2016 at 3:49 PM, Robinson, Paul via cfe-dev <
> cfe-dev at lists.llvm.org> wrote:
>
>> For my project, timing is everything.  We (and I could easily imagine,
>> for many downstream projects) lead time is important.
>>
>
> In Chromium land, we've so far been able to use the same compiler we
use
> to build Chrome to build clang. Currently that's MSVS2015 update 2, and
it
> took quite a while to update from 2013 to 2015 due bugs in 2015 and
> whatnot. So I agree that it's useful to support older MSVS versions for
> some time. For this reason, requiring update 3 would be inconvenient for
> us, but 2015u2 would be no problem by now. It would've been a problem
if
> 2015 had been required shortly after it was released.
>
> Nico
> _______________________________________________
> cfe-dev mailing list
> cfe-dev at lists.llvm.org
> http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-dev
>
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I've heard from another group within Sony that they had "a number of
problems" with VS2015 update 2, and strongly recommend going straight to
update 3.  My immediate team has initiated a request but it hasn't gone
through yet.
--paulr

From: James Molloy [mailto:james at jamesmolloy.co.uk]
Sent: Wednesday, August 03, 2016 1:54 AM
To: Nico Weber; Robinson, Paul
Cc: llvm-dev; cfe-dev at lists.llvm.org
Subject: Re: [cfe-dev] [llvm-dev] Revisiting our informal policy to support two
versions of MSVC

Hi,

This sounds like a decent idea to me. However we use 2013 for all our windows
builds at the moment and it will take around 2 weeks to upgrade the
installations on our cluster. We're pushing this hard to get it done soon so
we don't get caught short, but a grace period would be much appreciated.

Cheers,

James

On Tue, 2 Aug 2016 at 21:24 Nico Weber via cfe-dev <cfe-dev at
lists.llvm.org<mailto:cfe-dev at lists.llvm.org>> wrote:
On Tue, Aug 2, 2016 at 3:49 PM, Robinson, Paul via cfe-dev <cfe-dev at
lists.llvm.org<mailto:cfe-dev at lists.llvm.org>> wrote:
For my project, timing is everything.  We (and I could easily imagine,
for many downstream projects) lead time is important.

In Chromium land, we've so far been able to use the same compiler we use to
build Chrome to build clang. Currently that's MSVS2015 update 2, and it took
quite a while to update from 2013 to 2015 due bugs in 2015 and whatnot. So I
agree that it's useful to support older MSVS versions for some time. For
this reason, requiring update 3 would be inconvenient for us, but 2015u2 would
be no problem by now. It would've been a problem if 2015 had been required
shortly after it was released.

Nico
_______________________________________________
cfe-dev mailing list
cfe-dev at lists.llvm.org<mailto:cfe-dev at lists.llvm.org>
http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-dev
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I'd like to revisit this. As a person who spends a fair amount of time
monitoring our VS 2013 buildbots, I would say that I am ready to throw in
the towel on MSVC 2013. Since this discussion, I have committed five (!)
workarounds for MSVC 2013:

# in llvm
$ git log --author=rnk --grep=2013  --after='Aug 4 2016' --oneline
21a8ade Fix the MSVC 2013 build by using Elf_Word instead of making a local
typedef
27e101d Revert "Add an optional parameter with a list of undefs to
extendToIndices"
e8beddd Make vec_fabs.ll pass with MSVC 2013
ca77873 [AMDGPU] Give enum an explicit 64-bit type to fix MSVC 2013 failures

# in clang
$ git log --author=rnk --grep=2013  --after='Aug 4 2016' --oneline
18235a5 Try to work around an MSVC 2013 bug around defaulted default ctors

I'm pretty sure I'm missing instances where I helped others commit
workarounds as well. So, I'd really like to drop 2013, probably sometime
next month.

That said, I'd also like to echo Paul's sentiment that it'd help if
people
were less adventurous in their uses of C++11. New language features may
look nice, but ultimately you may end up wasting my time and yours when I
come and revert your change.

On Thu, Aug 4, 2016 at 7:52 AM, Robinson, Paul via llvm-dev <
llvm-dev at lists.llvm.org> wrote:
> I've heard from another group within Sony that they had "a number
of
> problems" with VS2015 update 2, and strongly recommend going straight
to
> update 3.  My immediate team has initiated a request but it hasn't gone
> through yet.
>
> --paulr
>
>
>
> *From:* James Molloy [mailto:james at jamesmolloy.co.uk]
> *Sent:* Wednesday, August 03, 2016 1:54 AM
> *To:* Nico Weber; Robinson, Paul
> *Cc:* llvm-dev; cfe-dev at lists.llvm.org
> *Subject:* Re: [cfe-dev] [llvm-dev] Revisiting our informal policy to
> support two versions of MSVC
>
>
>
> Hi,
>
>
>
> This sounds like a decent idea to me. However we use 2013 for all our
> windows builds at the moment and it will take around 2 weeks to upgrade the
> installations on our cluster. We're pushing this hard to get it done
soon
> so we don't get caught short, but a grace period would be much
appreciated.
>
>
>
> Cheers,
>
>
>
> James
>
>
>
> On Tue, 2 Aug 2016 at 21:24 Nico Weber via cfe-dev <cfe-dev at
lists.llvm.org>
> wrote:
>
> On Tue, Aug 2, 2016 at 3:49 PM, Robinson, Paul via cfe-dev <
> cfe-dev at lists.llvm.org> wrote:
>
> For my project, timing is everything.  We (and I could easily imagine,
>
> for many downstream projects) lead time is important.
>
>
>
> In Chromium land, we've so far been able to use the same compiler we
use
> to build Chrome to build clang. Currently that's MSVS2015 update 2, and
it
> took quite a while to update from 2013 to 2015 due bugs in 2015 and
> whatnot. So I agree that it's useful to support older MSVS versions for
> some time. For this reason, requiring update 3 would be inconvenient for
> us, but 2015u2 would be no problem by now. It would've been a problem
if
> 2015 had been required shortly after it was released.
>
>
>
> Nico
>
> _______________________________________________
> cfe-dev mailing list
> cfe-dev at lists.llvm.org
> http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-dev
>
>
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>
>
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