Re: [Qemu-devel] [PATCH v3] glib: fix g_poll early timeout on windows

[Stanislav Vorobiov]

Hi,

Yes it's probably the cause, thanks.

On 05/07/2014 12:49 PM, Alex Bligh wrote:
> 
> On 7 May 2014, at 09:36, Stanislav Vorobiov wrote:
> 
>> Hi,
>>
>> Hm, but (int)res expression is not unsigned, it's signed. I've also had this 
>> warning,
>> but with this expression: (res < WAIT_OBJECT_0), that's why I put (int) 
>> there. Could it be that
>> for some reason your compiler treats "int" and "unsigned int", that would be 
>> really strange though...
> 
> I suspect the problem is that WAIT_OBJECT_0 is defined as an unsigned long:
> 
> #define WAIT_OBJECT_0       ((STATUS_WAIT_0 ) + 0 )
> 
> #define STATUS_WAIT_0       ((DWORD)0x00000000L)
> 
> So IIRC under the 'usual conversions', and int compared with it will be cast 
> to an unsigned long too.
> 
> I think you want to cast WAIT_OBJECT_0 to a long or similar.
> 
> Alex
> 
> 
>> On 05/07/2014 12:02 PM, Stefan Hajnoczi wrote:
>>> On Fri, Apr 18, 2014 at 08:24:03PM +0400, Stanislav Vorobiov wrote:
>>>
>>> Please fix the following compiler warning with gcc 4.8.2:
>>>
>>>> +        } else if ((res == WAIT_TIMEOUT) || (res == WAIT_IO_COMPLETION) ||
>>>> +                   ((int)res < WAIT_OBJECT_0) ||
>>>> +                   (res >= (WAIT_OBJECT_0 + nhandles))) {
>>>> +            break;
>>>> +        }
>>>
>>> util/oslib-win32.c: In function 'g_poll_fixed':
>>> util/oslib-win32.c:324:21: warning: comparison of unsigned expression < 0 
>>> is always false [-Wtype-limits]
>>>                    ((int)res < WAIT_OBJECT_0) ||
>>>                                      ^
>>>
>>
>>
>>
>