g++ and aliasing bools

[Joe Buck]

Robert writes:

> You are still hung up on the idea that the problem we are trying to
> solve is to determine whether two items are aliased. That's NOT the
> problem here.  THe problem is to determine sets of items that are
> provably not aliased. These are quite different problems, and you are
> getting confused between them.

Sorry I didn't see this message before I wrote mine; Robert expresses it
exactly correctly.  And all other problems gcc may encounter that involve
undecidability get treated in the same way (handle cases you can't analyze
conservatively).