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Fix data race on lazy initialization of function pointers in SimSIMD dispatch#102132

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alexey-milovidov merged 2 commits intoClickHouse:masterfrom
vitlibar:fix-data-race-on-lazy-init-in-simsimd
Apr 10, 2026
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Fix data race on lazy initialization of function pointers in SimSIMD dispatch#102132
alexey-milovidov merged 2 commits intoClickHouse:masterfrom
vitlibar:fix-data-race-on-lazy-init-in-simsimd

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@vitlibar vitlibar commented Apr 8, 2026 •
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Fix data race on lazy initialization of function pointers in SimSIMD dispatch
PR to ClickHouse/SimSIMD: #26

Fixes #101968

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clickhouse-gh Bot commented Apr 8, 2026 •
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Workflow [PR], commit [eff7edd]

Summary: ✅

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Summary

This PR updates contrib/SimSIMD from e3714957 to e81e1c2d to pull upstream fixes for lazy dispatch initialization races and MemorySanitizer false positives in ARM SVE reductions. I reviewed the submodule delta (5 upstream commits, 6 files touched) and found no correctness, safety, or compatibility issues in ClickHouse integration. The change is narrowly scoped to dependency update and looks safe to merge.

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  • Status: ✅ Approve

@clickhouse-gh clickhouse-gh Bot added pr-not-for-changelog This PR should not be mentioned in the changelog submodule changed At least one submodule changed in this PR. labels Apr 8, 2026
@vitlibar vitlibar requested a review from Copilot April 8, 2026 21:25
Copilot AI reviewed Apr 8, 2026
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Copilot reviewed 1 out of 1 changed files in this pull request and generated no comments.

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alexey-milovidov commented Apr 9, 2026

The MSan stress test failure (MemorySanitizer: use-of-uninitialized-value, STID 4179-5154 or 4148-3044) is a known pre-existing issue unrelated to this PR. Fix: #102158

@vitlibar vitlibar force-pushed the fix-data-race-on-lazy-init-in-simsimd branch from a8d90ca to 97a69a1 Compare April 9, 2026 09:46
@vitlibar vitlibar marked this pull request as ready for review April 9, 2026 09:46
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vitlibar commented Apr 9, 2026 •
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This PR correctly sets the submodule pointer to the HEAD commit of branch ClickHouse/v6.5.15 - thus in fact it enables three changes and not one:

@vitlibar vitlibar added the 🍃 green ci 🌿 Fixing flaky tests in CI label Apr 9, 2026
@vitlibar vitlibar mentioned this pull request Apr 9, 2026
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alexey-milovidov commented Apr 10, 2026

The Hung check failure is fixed by #102008 and #102010, let's update the branch

@alexey-milovidov alexey-milovidov self-assigned this Apr 10, 2026
@alexey-milovidov alexey-milovidov merged commit 9501061 into ClickHouse:master Apr 10, 2026
163 of 164 checks passed
@robot-ch-test-poll4 robot-ch-test-poll4 added the pr-synced-to-cloud The PR is synced to the cloud repo label Apr 10, 2026
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🍃 green ci 🌿 Fixing flaky tests in CI pr-not-for-changelog This PR should not be mentioned in the changelog pr-synced-to-cloud The PR is synced to the cloud repo submodule changed At least one submodule changed in this PR.

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ThreadSanitizer: data race (STID: 2410-3957)

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