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Re: Is this a gcc bug?
Falk Hueffner wrote:
> Michael Eager <email@example.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.
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