Aliasing brokenness (Was: Re: [patch RFC] SH: Use FRAME_GROWS_DOWNWARD)

Andreas Schwab
Wed Jul 20 21:13:00 GMT 2005

Gabriel Dos Reis <> writes:

> Is the conclusion that a presence of "potentially unused" union that
> contains two structures with the same prefix destroys non-aliasing
> assumptions?

IMHO the third example in gives a strong hint at that.  AFAIU the
second fragment becomes valid as soon as declaration of the union is moved
before function f.


Andreas Schwab, SuSE Labs,
SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."

More information about the Gcc-patches mailing list