AntoinePrv commented on PR #50611: URL: https://github.com/apache/arrow/pull/50611#issuecomment-5058211598
The best hypothesis I have goes as follows (this was heavily AI assisted): We had a similar problem with the ODR violation, but the cause is different here (latest xsimd has the ODR fix). The issue arise during LTO where the fags `-msve-vector-bits=128` and `-msve-vector-bits=256` get conflated, resulting in the 256 version making 128 bits assumptions. The supporting evidence is the presence of `ptrue p7.b, vl16` in `unpack_sve256`: this sets a predicate (all true since we don't use them) only to 16 bytes (128 bits). While there is some uncertainty in this diagnosis, the presence of both `sve128` and `sve256` is an extremely likely enabler of the issue. Given I had plan to remove the SVE128 because it did not bring much over Neon, landing this fix has no drawbacks. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
