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I maintain the membarrier(2) system call, which provides a MEMBARRIER_CMD_PRIVATE_EXPEDITED_SYNC_CORE command for this purpose. It's been there since Linux 4.16. It can be configured out (CONFIG_MEMBARRIER=n), but it's enabled by default. Calling this after dlclose() in glibc would prevent this issue. Is it handled in some other way, or should we open a bugzilla entry to track this ? Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com