C++: Fix queries after #20126#936

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MathiasVP wants to merge 2 commits intogithub:nextfrom

MathiasVP:better-global-variable-flow-follow-up

Commits on Jul 25, 2025

C++: Block flow into thread-specific storage creating functions (i.e., *almost* the sources of the query) to remove false negatives.
MathiasVP
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C++: Accept test changes to another query.
MathiasVP
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