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? The code is rather complex so I'm trying to save time asking here first. I guess stdint.h cannot always define a uint64_t type, for example if the platform does not support it?
Alternatively, bitrotate.m4 could check for uint64_t and enable rotl64 and rotr64 functions only if the type exists. That may be cleaner anyway. /Simon
