Patch for MinGW-W64 port

[Nikos Mavrogiannopoulos]

On 03/22/2012 09:26 PM, Eli Zaretskii wrote:

> 64-bit Windows uses the LLP64 model, so `unsigned long' is a 32-bit
> type.  By contrast, ptrdiff_t is a (signed) 64-bit type.
> 
>>> +    $ac_cv_sizeof_long_long)
>>> +      AC_DEFINE([GNUTLS_POINTER_TO_INT_CAST], [(long long)],
>>> +                [Additional cast to bring void* to a type castable to int.])
>>> +      ;;
>> Why use long long for pointer to int? Isn't in this platform
>> sizeof(void*)==sizeof(long)?
> No, see above.  On 64-bit Windows, sizeof(void *) == sizeof(long long)


Ah, ok. I've applied a slightly modified version of it.

regards,
Nikos