Re: [Qemu-devel] [PATCH v2 06/13] qemu-thread: add simple test-and-set spinlock

[Sergey Fedorov]

On 09/04/16 00:31, Richard Henderson wrote:
> On 04/08/2016 02:26 PM, Paolo Bonzini wrote:
>>
>> On 08/04/2016 23:24, Alex Bennée wrote:
>>>> Except that quite a lot of hosts can only (efficiently) do atomic 
>>>> operations on
>>>> a minimum of 4 byte quantities.  I'd rather continue to use int here.
>>> I suspect bool == unsigned int underneath. But having true/false and 0/1 
>>> mixed up
>>> gets confusing even if they are equivalent.
>> Sometimes sizeof(bool) == 1.
> sizeof(bool) == 1 everywhere except MacOSX, where it's 4.
>

Hm, that's too strange:

$ gcc a.c
a.c: In function ‘main’:
a.c:6:5: warning: format ‘%d’ expects argument of type ‘int’, but
argument 2 has type ‘long unsigned int’ [-Wformat=]
     printf("%d\n", sizeof(bool));
     ^
$ ./a.out
1


Kind regards,
Sergey