Does anyone know how to make the compiler not overlay unused subroutine parameter locations with local variables? It's obvious to just set it to something after the point in which you want to look at it. But, optimization 0, doesn't prevent it.
The best way to avoid that is to avoid having any unused parameters in the first place. Or if you have to have them, say, because there's some externally forced API spec to work with, avoid looking at things that have no useful meaning.