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Re: Sorry to mention aliasing again, but is the standard IN6_ARE_ADDR_EQUAL really wrong?


Hi,

On Sun, 10 Jan 2010, Dave Korn wrote:

>   Ok.  So if I had four ints, and I wanted to cast the pointers to char 
> and compare them as 16 chars, that would be OK, because the chars would 
> alias the ints; but in this case, where they started as chars and I cast 
> them to ints, those ints don't alias against the original chars.  Is 
> that an accurate precis?

Yes, this is correct.  Many people are surprised by that, as they often 
"learned" that 'char' is the catch-all escape from aliasing problems.  
This is only true in one direction (accessing anything as chars), but not 
in the other (accessing chars as something else).


Ciao,
Michael.


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