Re: [Bug rtl-optimization/21402] wrong-code with inlining and type-punned pointer

[Andrew Pinski <pinskia at physics dot uc dot edu>]

On May 21, 2005, at 6:28 PM, schlie at comcast dot net wrote:

> ------- Additional Comments From schlie at comcast dot net  2005-05-21 
> 22:28 -------
> (In reply to comment #6)
> > Subject: Re:  wrong-code with inlining and type-punned pointer
> >
> > Sorry, I don't see that implication.  However, GCC already has a
> > switch for tuning off such comparison.
>
> - Then what is the purpose of the this portion of the standard, if
>    not to clarify the intent that lvalues which only differ in signness
>    or otherwise compatible qualifications may validly alias each other?
>
>   (this is an honest question, I'm not trying to be difficult)

unsigned and signed types are already in the same aliasing set.
Just their pointers are in different aliasing set as allowed by the
standard and this is where the problem is in the code in this bug.

Thanks,
Andrew Pinski