[LLVMdev] Self-hosting failure in ARM again

[Ahmed Bougacha]

On Wed, Mar 4, 2015 at 8:06 AM, Renato Golin <renato.golin at linaro.org> wrote:
> Folks,
>
> It seems we got the same issue with Clang alignment as before:
>
> http://lab.llvm.org:8011/builders/clang-cmake-armv7-a15-selfhost/builds/3025
> http://lab.llvm.org:8011/builders/clang-cmake-armv7-a15-selfhost-neon/builds/485
> http://lab.llvm.org:8011/builders/clang-cmake-thumbv7-a15-full-sh/builds/118

Hmm, are these actually alignment-related?  They all seem to be the
same assert failing:

    Assertion `(!DD->isTrivial() || DD->hasAttr<DLLExportAttr>()) &&
"Should not emit dtor epilogue for non-exported trivial dtor!"'
failed.

I'm tempted to say the CommandLine changes triggered some clang bug?

> Commits between 231213 and 231255.
>
> There are a few issues that could have brought it:
>  * Seth's changes to Clang (unlikely)
>  * Michael's changes to DAGCombiner (likely)
>  * David's generic changes in LLVM (unlikely)
>
> I'll be bisecting this like I did earlier, but I'd like to keep you
> guys posted of the potential reverts, since this is not jut breaking
> tests, but breaking Clang self-hosting (which cost us weeks during the
> release).
>
> Ahmed,
>
> You have a better idea what the real problem is. I think maybe we
> should bump its priority up again, or this will keep popping every
> month.
>
> Did you file a bug?

Yep, http://llvm.org/bugs/show_bug.cgi?id=22728

Good luck with the bisecting!

-Ahmed

> cheers,
> --renato