Re: Is this code safe?

Pavan Deolasee <pavan.deolasee@gmail.com> writes:
> Can some kind of compiler optimisation reorder things such that the "else
> if" expression is evaluated using the old, uninitialised value of optval?

Any such behavior is patently illegal per the C standard.  Not that that's
always stopped compiler writers; but I think you might be looking at a
compiler bug.  We'd need more context about the exact platform, compiler,
etc.
        regards, tom lane