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Re: GCC aliasing rules: more aggressive than C99?

On 01/05/2010 03:23 PM, Vincent Lefevre wrote:
> 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!

Try reading it.  This is Clause 7.

Andrew.
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