Is the construction unsigned long long permitted?

Question

Is the construction unsigned long long permitted? And is there anything like unsigned long double?

Giving it a try not necissarily is a good option: Compilers sometimes provide extended types which are non-standard. — johannes, Mar 10 '13 at 13:16
@johannes Yes, but *not* giving it a try before asking is not any better. — Masked Man, Mar 10 '13 at 13:53

score 4 · Accepted Answer · answered Mar 10 '13 at 13:13

4

unsigned long long is fine. (Technically, it's been around since C99, but only since C++11, but every major C++ compiler has been implementing it for quite a long time already.)

There is no such thing as unsigned long double. Floating point types (at least those available in any language I can think of, and certainly those described by IEEE754 and the C standard) are always signed.

answered Mar 10 '13 at 13:13

us2012

16,083
3
46
62

3

The C spec explicitly says that there are no unsigned floating-point types. – nneonneo Mar 10 '13 at 13:13

score 4 · Answer 2 · edited May 23 '17 at 10:32

Yes, unsigned long long is permitted because it declares a variable of type long long that is also unsigned. The unsigned keyword can be applied to any integer type, and long long is indeed an integer type.

There is no such thing as unsigned long double because long double is a floating point type (as opposed to an integer type), and there is no such thing as unsigned floating point types (reference 1, reference 2).

score 0 · Answer 3 · answered Mar 10 '13 at 13:15

0

According to this here, there is aunsigned long long but only in C++ 11. About unsigned long double I am not sure.
Check out the reference,

answered Mar 10 '13 at 13:15

bash.d

13,029
3
29
42

... yeah, but it's been in C since `C99` and every major C++ compiler has been implementing it for years even though it wasn't in the standard until `C++11`. – us2012 Mar 10 '13 at 13:27

Is the construction unsigned long long permitted?

3 Answers3