Is this a gcc bug?

[Michael Eager]

Falk Hueffner wrote:
> 
> Michael Eager <eager@mvista.com> writes:
> 
> > My sugguestion:
> >
> >       undefined behavior:  value of expression using 'x' is undefined
> 
> This would seem to imply that the behaviour is undefined because one
> uses an undefined value. But that's not the case: the standard says
> program behaviour is undefined even if you say x = ++x and never look
> at x again. (At least IIRC.)

It is the result of the expression (including any side effects) which is 
undefined.  An expression has a value, even if you never use it.

There are many constructs with undefined behavior.  Some can be
recognized at compile time; most cannot.  

-- 

Michael Eager
Senior Tools Developer	  Phone: (408) 328-8426
MontaVista Software, Inc.   Fax: (408) 328-9204
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