testing consistency

[Joe Buck]

> My initial concern here is that there were mistakes in the arguments.
> People were claiming that H.J.'s patch was changing behaviour, when in
> fact it was restoring behaviour that was lost when we added the toplevel
> directory.  If we choose not to accept H.J.'s patch, then we are deciding
> to change how gcc operates.

Even if gcc is "right", perhaps egcs and gcc should not have the same
behavior in this case.  The official compiler going in /usr is one thing,
the experimental egcs compiler going in /usr is quite another.

> Incidentally, if we don't accept H.J.'s patch, then we need to fix the
> gcc/configure.in file to avoid conflicts over the default value of prefix.

Just use /usr/local everywhere.  Conflict gone.  (but I think gcc should
work that way too).