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Re: GCC aliasing rules: more aggressive than C99?

On 2010-01-05 10:31:13 +0000, Andrew Haley wrote:
> "An object shall have its stored value accessed only by an lvalue
> expression that has one of the following types:
> 
> but
> 
>  (union u*)&i
> 
> is not a legal lvalue expression because the dereference is undefined
> behaviour.  You may only dereference a pointer as permitted by 6.3.2.3.

For the same reason, (char *) &i could not be dereferenced, and this
would break a lot of code!

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Vincent Lefèvre <vincent@vinc17.net> - Web: <http://www.vinc17.net/>
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Work: CR INRIA - computer arithmetic / Arénaire project (LIP, ENS-Lyon)
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