[3.3] Followup to C++ forced unwinding

[Gabriel Dos Reis]

Mike Harrold <mharrold@cas.org> writes:

| But only if the implicit rethrow happens when a cancellation exception has
| been caught in the catch (...) block. Other exceptions _must_ be allowed
| to fall off the end of the block...

I believe it is important to remember that C++ is also a "glue"
language meaning that it is also used to pack different applications
together.  One implication is that it ought to be possible for a C++
program to catch exceptions from foreign languages.  I cannot imagine
that the notion of "ghost" exceptions will make it.

-- Gaby