I had this assigned to Alfredo for a while, but he hasn't replied to the tracker at all, so I suspect he's not around. I'll commit this now to prevent crashes. Some of the code in the glare node assumed that all buffers will be 4 channel RGBA, when in fact it was possible to give it a VEC3, such as a spec pass with no alpha, which would crash it. This fix just duplicates the input to a new temporary RGBA buffer to work on, if it's not already RGBA.