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Re: More fun with aliasing - removing assignments?

Diego Novillo <dnovillo@redhat.com> writes:

> Does the language allow the creation of address locations out of
> arbitrary integer values?

Yes.

    6.3.2.3 Pointers

    5 An integer may be converted to any pointer type. [...]

>  Is the dereference of such an address a defined operation?

It is implemetation-defined.

    [...] Except as previously specified, the result is
    implementation-defined, might not be correctly aligned, might not
    point to an entity of the referenced type, and might be a trap
    representation.

Also, the integer may have been the result of casting a valid pointer, in
which case the operation is fully defined (assuming the integer is wide
enough).

Andreas.

-- 
Andreas Schwab, SuSE Labs, schwab@suse.de
SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
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