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Date: Thu, 20 Aug 2009 11:22:50 +0200
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Subject: [Qemu-devel] Re: [PATCH 02/29] Introduce QInt
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To: Avi Kivity <avi@redhat.com>
Cc: aliguori@us.ibm.com, qemu-devel@nongnu.org, Luiz Capitulino <lcapitulino@redhat.com>

On 08/20/2009 09:51 AM, Avi Kivity wrote:
> On 08/20/2009 02:07 AM, Luiz Capitulino wrote:
>> QInt is a high-level data type that can be used to store integers
>> and perform type-safe conversions.
>>
>> The following functions are available:
>>
>> - qint_from_int() Create a new QInt from an int
>> - qint_from_int64() Create a new QInt from an int64_t
>> - qint_to_int() Export QInt to int
>> - qint_to_uint64() Export QInt to uint64_t
>> - qint_to_uint32() Export QInt to uint32_t
>
> Why aren't the conversion functions symmetrical?

I guess because an uint32_t would extend directly to uint64_t.  But, the 
solution would be to drop qint_from_int (since also an int32_t extends 
correctly to uint64_t [1]) and rename qint_from_int64:

Paolo

[1] example program to avoid getting into C standardese:

#include <stdint.h>

int f(uint64_t i)
{
   printf ("%lld\n", i);
}

int main()
{
   int32_t i = -1<<31;
   uint32_t j = 1 << 31;
   f(i);
   f(j);
}