Andrew Haley <aph@xxxxxxxxxx> writes: > Ian Lance Taylor writes: > > > > All objects shared between threads need to protected by a mutex, or by > > some other type of memory barrier. > > It's an interesting contention -- that in GNU/Linux userspace there > are essentially no legitimate uses for volatile. Hmmmm... There is one legitimate use: the C standard blesses the specific case of "volatile sig_atomic_t". A signal handler can reliably access a variable of that type. I don't think there is any other reason to use volatile in userspace. It simply does not mean what it seems to mean. Ian
