[llvm-dev] Problem with clang optimizer?

Anton Afanasyev via llvm-dev llvm-dev at lists.llvm.org
Tue Oct 26 09:43:07 PDT 2021


Hi Uri,
sorry for confusing you! I didn't tackle this enough (and had an old
strange clang-13 installation on a weird box).
Your issue is actually reproduced on godbolt with "-march=skylake" option:
https://godbolt.org/z/jaMP3W1cn .
That means this bug is veiled only in particular. As Dimitry said, the next
clang-13.0.1 release should grasp the whole fix.
  Thanks,
    Anton

вт, 26 окт. 2021 г. в 16:40, Blumenthal, Uri - 0553 - MITLL <uri at ll.mit.edu
>:

> Ok, I found that confusion comes from the different binaries supplied as
> "version 13", see below.
>
>
>
> Now I am confused.
>
>
>
> Does it mean that distributions (Ubuntu on Linux, Macports on MacOS, etc.)
> took *pre-release* (aka, still-beta) LLVM/Clang and released it as
> Clang-13?
>
>
>
> Or that LLVM or Clang were patched after being released, *without
> updating the version* numbers?
>
>
>
> > So, requested Clang, but compiled with GCC???
>
> Godbold actually uses Clang here, "-gcc-toolchain" is just its option to
> provide GCC installation.
>
>
>
> I do not understand the above – that “checkbox-button” seems to be named
> “All compilation options” for the *currently selected*
> compiler/toolchain…?
>
> On the other hand, I’m probably not the main customer of that tool, so my
> understanding is not crucial. ;-)
>
>
>
> Yes, I've managed to reproduce it too on my ubuntu box with "clang-13"
> package installed:  .  .  .  .  .
>
> But that's not the clang-13 used by me and godbold, tagged as
> llvmorg-13.0.0 and announced on 4 October 2021. The ubuntu-packaged
> clang-13 uses e5f2898bc751 tip commit pushed on 27 March 2021, so it's an
> older version.
>
>
>
> I hear you – but what about Mac? Macports Clang-13.0.0 was released only a
> couple of days ago. I don’t know how to check its commit level, but I
> strongly doubt it’s as dated as, e.g., Ubuntu release…
>
>
>
> If you want to get subject issue fixed, you can use clang-13 from here:
> https://github.com/llvm/llvm-project/releases/tag/llvmorg-13.0.0, for
> instance, here is apple-darwin version:
> https://github.com/llvm/llvm-project/releases/download/llvmorg-13.0.0/clang+llvm-13.0.0-x86_64-apple-darwin.tar.xz
>
>
>
> I do, but I much prefer that Macports maintains “big” packages on my
> machines, and LLVM-Clang definitely qualify. Thus, I’d rather not track
> llvm-project on GitHub myself.
>
>
>
> Can I hope that the fix Dimitry mentioned, will be in 13.0.1 that will
> (hopefully, eventually) filter downstream?
>
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20211026/3ce3a522/attachment.html>


More information about the llvm-dev mailing list