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Re: PATCH: `__norestrict' type qualifier


"Jerry Quinn" <jquinn@nortelnetworks.com> writes:

|> Isn't the alignment precision a more general problem?  If I understand what is
|> allowed by the standard (by following the recent threads) the following is
|> allowed to work correctly, because the incorrect pointer is only used to hold
|> the value and you then read it through a pointer of the correct type.
|> 
|> short s = 5;
|> long *pl;
|> short *ps;
|> pl = &s;
|> ps = (short *)pl;

The second last line contains a constraint violation (assignment of
incompatible pointer types), so anything can happen.  But if you add the
required cast then "ps == &s" must be true afterwards.

-- 
Andreas Schwab                                  "And now for something
schwab@suse.de                                   completely different."
SuSE GmbH, Schanzäckerstr. 10, D-90443 Nürnberg


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