Casting to pointer from integer

I'm porting my code over to 64-bit and get the "casting to pointer from integer of different size" warning from:

Code:

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(void *)(int)foo

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I can understand it warning about a loss of information (casting down), but casting up isn't dangerous and the compiler should no more complain than had I done (long long)(int). Anyways I suppose that's compiler philosophy. What I need to know is how do I shut it up without resorting to #ifdef's?
This does not work:

Code:

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(void *) (sizeof(void *) == sizeof(long long) ? (long long)foo : foo)

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only other alternative I can think of is -Wno-int-to-pointer-cast

What if you cast to long long and then cast to void*? But that looks like a hack, heheh.

Quote:

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Originally Posted by laserlight

What if you cast to long long and then cast to void*? But that looks like a hack, heheh.

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yep, I should have mentioned I don't want to anger my 32-bit build either :)

But I remembered reading something from opengroup.org on this, and it came back to me: intptr_t is the answer! It's an integer type with the same size as a pointer:

Code:

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(void*)(intptr_t)foo

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Why do you need to cast a pointer to an integer in the first place, though?