How do you specify a 64 bit unsigned int const 0x8000000000000000 in VS2008?

Question

I read about the Microsoft specific suffix "i64" for integer constants. I want to do an UNsigned shift to a ULONGLONG.
ULONGLONG bigNum64 = 0x800000000000000i64 >> myval;

In normal C, I would use the suffix "U", e.g. the similar 32 bit operation would be
ULONG bigNum32 = 0x80000000U >> myval;

I do NOT want the 2's complement sign extension to propogate through the high bits. I want an UNSIGNED shift on a 64 bit const number. I think my first statement is going to do a SIGNED shift right.

I tried 0x800000000000000i64U and 0x800000000000000u64 but got compiler errors.

Answer 1

You can use the suffix ull, which is the standard (C99 and C++0x) way to specify an unsigned long long integer literal, and a long long is at least 64 bits.