Might be true for UBSan and LSan, that have a moderate impact, but not for ASan and certainly not for MSan or TSan. (as a _very_ crude approximation, with UBSa

Might be true for UBSan and LSan, that have a moderate impact, but not for ASan and certainly not for MSan or TSan. (as a _very_ crude approximation, with UBSan on, you have the performance of Java or Go, and with the other sanitizers you get closer to Ruby territory) You can't combine the sanitizers anyway. They're really designed to be enabled for a testsuite and debug builds.