[crac] RFR: 8372863: [CRaC] Fix glibc IFUNC for AVX_Fast_Unaligned_Load

Tue Dec 2 11:02:00 UTC 2025

glibc derives `AVX_Fast_Unaligned_Load` from CPU features but it is based on hardware CPU features and so disabling a CPU feature required for `AVX_Fast_Unaligned_Load` will not disable `AVX_Fast_Unaligned_Load` itself and it needs an explicit `GLIBC_TUNABLES` environment variable disabling.

There is a whole such category of 'preferred' bits. I hope no other bit causes crash (as they are there primarily for performance benefits) but that should be still verified.

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Commit messages:
 - fix glibc preferred bits

Changes: https://git.openjdk.org/crac/pull/277/files
  Webrev: https://webrevs.openjdk.org/?repo=crac&pr=277&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8372863
  Stats: 26 lines in 2 files changed: 20 ins; 1 del; 5 mod
  Patch: https://git.openjdk.org/crac/pull/277.diff
  Fetch: git fetch https://git.openjdk.org/crac.git pull/277/head:pull/277

PR: https://git.openjdk.org/crac/pull/277