Is LL defined anywhere in the standard (hard term to come by)?
ideone accepts the code
int main()
{
std::cout << sizeof(0LL) << std::endl;
std::cout << sizeof(0);
}
and prints
8
4
But what does it mean?
Answer
It is specified in Paragraph 2.14.2 of the C++11 Standard:
2.14.2 Integer literals
[...]
long-long-suffix: one of
ll LL
Paragraph 2.14.2/2, and in particular Table 6, goes on specifying the meaning of the suffix for decimal, octal, and hexadecimal constants, and the types they are given.
Since 0 is an octal literal, the type of 0LL is long long int:
#include <type_traits>
int main()
{
// Won't fire
static_assert(std::is_same<decltype(0LL), long long int>::value, "Ouch!");
}