Bug#1077068: llvm-toolchain-17 FTBFS with gcc-14 on arm64

[NoisyCoil]

Package: llvm-toolchain-17
Version: 1:17.0.6-12
Severity: important
Tags: ftbfs upstream
X-Debbugs-Cc: noisycoil at tutanota.com

Dear Maintainer,

llvm-toolchain-17 fails to build from source with gcc-14 on arm64 due to this upstream bug:
https://github.com/llvm/llvm-project/issues/78691. A fix was merged to v18
(https://github.com/llvm/llvm-project/pull/78704), but AFAICS the patch was not backported
to v17. Since the bug more widely affects libclang, I expect other packages to FTBFS with
gcc-14 + llvm-17 on arm64. One such package is mesa (this is how I came across this bug).

Best,

NoisyCoil

P.S.: I checked that llvm-16 still builds with gcc-14.