Cannot obtain value of local or argument as it is not available at this instruction pointer, possibly because it has been optimized away

Question

Visual Studio 2010 kills (there is no other word) data in one of the arguments of the function in the unsafe block. What could cause this error? The following message shows

Answer 1

I just ran into this and I was running under Release build configuration instead of Debug build configuration. Once I switched back to Debug my variable showed in the watch again.