On 15/10/2024 08:12, Thiago Adams wrote:
> On 14/10/2024 08:14, Thiago Adams wrote:
>> On 14/10/2024 02:00, Tim Rentsch wrote:
>>> Kaz Kylheku <643-408-1753@kylheku.com> writes:
>>>
>>>> On 2024-10-13, Thiago Adams wrote:
>>>>
>>>>> The algorithm for C initialization as described in the standard
>>>>> and implemented in gcc allow this.
>>>>>
>>>>> struct X{
>>>>> int a,b,c;
>>>>> };
>>>>>
>>>>> int main()
>>>>> {
>>>>> struct X x = {.a=1,2,3,.a=1, 2, 3};
>>>>> }
>>>>>
>>>>> https://godbolt.org/z/7naedbEM6
>>>>>
>>>>> Basically, when a designed initializer is found the "cursor" goes
>>>>> to that member and the following members are initialized in
>>>>> order.
>>>>
>>>> I do not suspect that therw is an observable order. I.e. as
>>>> in a required order considered observable behavior.
>>>
>>> Have you checked to C standard to see what it says about that?
>
> I'm not only interested in this part, but since it raised some doubts, I
> decided to do some checks
>
> #include
>
> struct X {
> int i;
> };
>
> int f() {
> printf("f");
> return 1;
> }
>
> int main() {
> struct X x = {.i = f(), .i = f() };
> }
>
> https://godbolt.org/z/rf984cGMM
>
> There is a warning in this sample and f is called just once.
>
>
>
Forgot to say that I didn't find this part on the standard.
I think initialization is also very superficial on books.
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