syscall(2) returns long, not int. Says Clang: qfutex_linux_p.h:48:18: error: implicit conversion loses integer precision: 'long' to 'int' [-Werror,-Wshorten-64-to-32] int result = syscall(__NR_futex, addr, op | FUTEX_PRIVATE_FLAG, val, val2, addr2, val3); ~~~~~~ ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Don't truncate to int in _q_futex(), pass it as long into the few callers that care about the result. Amends the start of the public history, but not picking back all the way because the code moved around a lot. In 6.7 it found its current place. Pick-to: 6.8 6.7 Task-number: QTBUG-103528 Task-number: QTBUG-126219 Change-Id: I54ccaf5564bcaf38f05fab153b1b32379a66a178 Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>