int i= i ^ i ;
Since i
is an automatic variable (i.e it is declared in automatic storage duration), it is not (statically) initialized yet you're reading its value to initialize it (dynamically). So your code invokes undefined behaviour.
Had you declared i
at namespace level or as static
, then your code would be fine:
Namespace level
int i = i ^ i; //declared at namespace level (static storage duration)
int main() {}
Or define locally but as static
:
int main()
{
static int i = i ^ i; //static storage duration
}
Both of these code are fine, since i
is statically initialized, as it is declared in static storage duration.
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