Hi Fabian,
Thank you for the detailed analysis and for filing the upstream issue.
I'm looking into this from the ppc64el porter side and will test your
proposed fix in commit 133f997
(https://github.com/llvm/llvm-project/pull/184995/changes/133f997099485bdd326d4941addc4082509be553)
the missing uint128.h include and parser.h fix.
Will follow up once I've confirmed results on ppc64el.
The direction of 133f997 looks correct — it completes what PR
https://github.com/llvm/llvm-project/pull/136614
left incomplete without the ABI risk of
-DPPC_LINUX_DEFAULT_IEEELONGDOUBLE=ON.
Thanks,
Trupti
On 2026-03-06 17:48, Fabian Grünbichler wrote:
Source: llvm-toolchain-21
Severity: normal
Tags: upstream ftbfs patch
X-Debbugs-Cc: [email protected],
[email protected], [email protected]
User: [email protected]
Usertags: powerpcspe ppc64el
Hi!
I've been trying to backport llvm-toolchain-21 for Trixie for the past
few
weeks, because it is a requirement for backporting newer rustc
versions.
Unfortunately the build fails with floating point related errors. Those
errors
go away if I set -DPPC_LINUX_DEFAULT_IEEELONGDOUBLE=ON , but that is
the wrong
thing to do on Trixie which generally lacks IEEE long double..
I've tried various things, and ended up bisecting upstream LLVM which
points at
8437b7f5584765ad4f7885500647657714930fbb. That commit allegedly got
fixed[0],
but the fix seems incomplete (since it is included in 21.1.8 and that
is still
broken). I've now filed an issue[1] and PR[2] upstream after verifying
that
upstream main is also affected.
I'd appreciate input upstream from ppc experts, in particular whether
my
proposed changes (which do fix the package build when backporting to
Trixie!)
seem reasonable.
Thanks,
Fabian
0: https://github.com/llvm/llvm-project/issues/136596
1: https://github.com/llvm/llvm-project/issues/184994
2: https://github.com/llvm/llvm-project/issues/184995
