MDEV-32575 MSAN / Valgrind errors in test_if_cheaper_ordering upon re… #3762
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…aching in_predicate_conversion_threshold When converting an IN-list to a subquery, a temporary table stores the IN-list values and participates in join optimization. The problem is the bitmap of usable keys for the temporary table is initialized after the optimization phase, during execution. It happens when the table is opened via `ha_heap::open()`, after the subroutine `set_keys_for_scanning()` is called. Trying to access the bitmap earlier, during optimization, leads to MSAN/Valgrind errors. This fix removes the dependency on `set_keys_for_scanning()`. The key bitmap is now dynamically composed on demand in `keys_to_use_for_scanning()`, ensuring correctness without imposing strict call-order constraints.
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…aching in_predicate_conversion_threshold
Description
When converting an IN-list to a subquery, a temporary table stores the IN-list values and participates in join optimization. The problem is the bitmap of usable keys for the temporary table is initialized after the optimization phase, during execution. It happens when the table is opened via
ha_heap::open(), after the subroutineset_keys_for_scanning()is called. Trying to access the bitmap earlier, during optimization, leads to MSAN/Valgrind errors.This fix removes the dependency on
set_keys_for_scanning(). The key bitmap is now dynamically composed on demand inkeys_to_use_for_scanning(), ensuring correctness without imposing strict call-order constraints.Release Notes
When converting a large IN-list of values to a subquery there was a chance that optimizer accessed an uninitialized bitmap of indexes which could lead to wrong results or a crash
Basing the PR against the correct MariaDB version
mainbranch.PR quality check