[LCP]what value does the foo() return?

[Greg Black]

On 2004-01-06, Paul Gearon wrote:
> Greg Black wrote:
> > Incorrect
> >programs, e.g., those that exhibit undefined behaviour, are just
> >incorrect programs and their behaviour is not interesting.
> 
> I'll disagree here, but it really does depend on what you mean by 
> "interesting".

OK, but my definition excludes this sort of stuff, except when
I'm trying to debug (somebody else's) code ...

> So knowledge of undefined behaviour in a specific system can *sometimes* 
> help.  :-)

All sorts of (possibly quite arcane) knowledge can, and does,
help when it comes to debugging -- but this thread was about
putting the bugs in, not getting them out ...

> Back to the question of a missing return value in a return path; Ideally 
> your compiler will be good enough to spot undefined behaviour of such a 
> gross nature as this.  One should NEVER allow a warning like that to 
> continue to exist.

Indeed -- but it's worth noting that compilers are not required
to give diagnostics for undefined code.  Obviously, you'd tend
to choose a compiler that did go the extra mile to provide such
useful warnings; and it would be utter folly to ignore them.

Cheers, Greg