Yes I understand that foo() won't be called if you defined NDEBUG. But when compiling lthread, NDEBUG is not defined anywhere in the code / makefiles so it's gu

Yes I understand that foo() won't be called if you defined NDEBUG. But when compiling lthread, NDEBUG is not defined anywhere in the code / makefiles so it's guaranteed to be called and I want to assert the returned value.