Bug#1129949: llvm-toolchain-21: FTBFS on ppc64el on Trixie

[Fabian Grünbichler]

On Wed, Mar 11, 2026, at 12:30 PM, Trupti wrote:
> Hi Fabin,
>
> As a quick update, I was able to reproduce the issue on ppc64el with 
> Trixie. With below errors:
>
> [..]
>
> I'm currently testing the build with your suggested patches from 
> https://github.com/llvm/llvm-project/pull/184995
>
> I'm also discussing this with PowerPC toolchain experts to better 
> understand
> if there are any implications from the PPC side.
>
> I will update here once I have more information.

note that the complete disabling of printf float support was pretty
much rejected, but some alternatives were suggested in the review
discussion in the PR.

I am not sure yet how to proceed:
- upload llvm-toolchain-21 with ppc64el FTBFS, followed by rustc
  1.91, then fixing llvm-toolchain-21 and rebuilding rustc
- wait for the fix, potentially skip rustc 1.91 if that works, or
  arguing for an exception to allow uploading rustc 1.91 to bpo
  despite forky already having 1.92 by that time..

Fabian