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Re: in which we present an ugly hack to make sys/queue.h CIRCLEQ work



>> the C standard explicitly allows a pointer to a structure type to be
>> converted to the type of its first member and back, to another
>> structure type and back, or to char * or void * and back,
> I rather doubt that you can convert to a different structure type and
> back.

I feel sure Dennis Ferguson meant "to _a pointer to_ a different
structure type" there.

As I read it, the anti-alias rule doesn't actually say anything about
the pointers themselves, only about what results when you follow them;
if the code never followed the pointers, it could compare them just
fine without risk (though I'm going to ask my go-to C reference person
to check my reading on this point).

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