“A reference to a volatile field will not be treated as volatile” implications

Question

The following code

using System.Threading;

class Test
{
    volatile int counter = 0;
    public void Increment()
    {
        Interlocked.Increment(ref co         


        

Answer 1

Basically the warning is that when you pass a volatile field by reference, the calling code doesn't know to treat it in a volatile manner. For Interlocked.Increment that probably doesn't matter, due to the nature of the method - but then you don't need the variable to be volatile anyway if you're using Interlocked.

In general, I think I'd avoid mixing the two - if you're using Interlocked, do it everywhere (using Interlocked.CompareExchange(ref counter, 0, 0) to read it). I can't say I use volatile very often, personally. For simple counters I might use Interlocked, but I'm more likely to use a lock for most tasks.