Bug#1145420: highway: testsuite failure on riscv64 hardware with vector extension

[Adrian Bunk]

On Mon, Aug 24, 2026 at 10:09:42PM +0200, Aurelien Jarno wrote:
> Source: highway
> Version: 1.3.0-5.1
> Severity: important
> X-Debbugs-Cc: debian-riscv at lists.debian.org
> User: debian-riscv at lists.debian.org
> Usertags: riscv64
>...
> At this stage I haven't been able to fully fix the issue except by fully
> disabling RVV support. Nevertheless I would like to share my initial
> debugging attempts:
> 
> - Disabling "gcc-15.patch" fixes the issue.
> 
> - Building with -DHWY_CMAKE_RVV:BOOL=ON, instead on relying on runtime
>   detection fixes 4 of the issues, but adds an extra one:
> | 	126 - HwyBlockwiseTestGroup/HwyBlockwiseTest.TestAllZipLower/EMU128 (Failed)
> | 	696 - DotTestGroup/DotTest.TestAllDotF32BF16/RVV (Failed)
> 
> - With the current upstream HEAD with -DHWY_CMAKE_RVV:BOOL=OFF (so with runtime
> detection), I get:
> | 	365 - HwyInterleavedTestGroup/HwyInterleavedTest.TestAllLoadStoreInterleaved2/RVV (Failed)
> | 	367 - HwyInterleavedTestGroup/HwyInterleavedTest.TestAllLoadStoreInterleaved3/RVV (Failed)
> | 	369 - HwyInterleavedTestGroup/HwyInterleavedTest.TestAllLoadStoreInterleaved4/RVV (Failed)
> | 	697 - TupleTestGroup/TupleTest.TestAllCreate/RVV (Failed)
> | 	750 - MinMaxTestGroup/MinMaxTest.TestAllIndexOfExtremeInLongSpan/RVV (Failed)
> | 	774 - DotTestGroup/DotTest.TestAllDotF32BF16/RVV (Failed)
> | 	831 - IntDivTestGroup/IntDivTest.TestAllFloorDivision/RVV (Failed)
> 
> - With the current upstream HEAD with -DHWY_CMAKE_RVV:BOOL=ON, I get:
> | 	750 - MinMaxTestGroup/MinMaxTest.TestAllIndexOfExtremeInLongSpan/RVV (Failed)
> | 	774 - DotTestGroup/DotTest.TestAllDotF32BF16/RVV (Failed)
> | 	831 - IntDivTestGroup/IntDivTest.TestAllFloorDivision/RVV (Failed)
> 
> I have been able to reproduce the issue on a SpacemiT K1 CPU (like the
> buildds), a SpacemiT K3 CPU and using QEMU, so I think we can rule out a
> CPU bug.

For undocumented reasons, the main maintainer of this package (Mathieu) 
disabled unaligned access in experimental.

Does building with
  DEB_CXXFLAGS_MAINT_APPEND += -mstrict-align
make a difference?

> Regards
> Aurelien

cu
Adrian