Re: bitrotate

[Bruno Haible]

Ben Pfaff wrote:
> > There was a suggestion to support 64-bit rotates as well.  That would
> > use uint64_t.  Does stdint.m4 define some symbol that may be useful
> > here?
> 
> I believe that UINT64_C (for writing an unsigned 64-bit integer
> literal) is defined if and only if uint64_t is available.

Let's compare UINT64_C and UINT64_MAX: Both are indicators of uint64_t.
But UINT64_C is not defined if
  defined __cplusplus && ! defined __STDC_CONSTANT_MACROS
therefore I would use UINT64_MAX as a witness of uint64_t's presence.

Bruno