[haochengxia]

What does this PR do?

On GCC for ARM, the vendored xxHash 0.7.4 reads keys through a packed union. Without may_alias (introduced in xxhash 0.8.4), GCC assumes such a read cannot see a store of another type, which leads to test error.

47% tests passed, 8 tests failed out of 15
The following tests did not run:
         15 - testCLI (Skipped)
The following tests FAILED:
          2 - testSyntheticReader (SEGFAULT)
          5 - testSimulator (SEGFAULT)
          6 - testEvictionAlgo (SEGFAULT)
          7 - testMRC (Timeout)
          8 - testAdmissionAlgo (SEGFAULT)
          9 - testPrefetchAlgo (SEGFAULT)
         11 - testLcpReader (Failed)
         14 - testOracleTrace (Failed)

For a conservative fix, we do not upgrade to xxHash 0.8.4 but add may_alias annotation.

Type of change

• Bug fix
• New eviction / admission / prefetch algorithm
• New trace reader or trace format
• Performance improvement
• Documentation
• Build / CI
• Other:

[chatgpt-codex-connector]

Codex Review Summary: ✅ Completed

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-11-08T00:12:40.668105Z	606066b	PR opened

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