Index: lib/lsan/lsan_common_mac.cc =================================================================== --- lib/lsan/lsan_common_mac.cc +++ lib/lsan/lsan_common_mac.cc @@ -144,6 +144,11 @@ if (info.user_tag == VM_MEMORY_OS_ALLOC_ONCE) { ScanRangeForPointers(address, end_address, frontier, "GLOBAL", kReachable); + + // Recursing over the full memory map is very slow, break out + // early if we don't need the full iteration. + if (!flags()->use_root_regions || !root_regions->size()) + break; } // This additional root region scan is required on Darwin in order to