On Sun, Mar 29, 2020 at 5:00 AM Jeffrey Walton wrote: > > It looks like test-bitrotate.c is missing test cases. It is missing > the 32-bit rotl and rotr of 0-bits. > > The 0-bit rotate should tickle undefined behavior. > > If you want to clear the undefined behavior, then use this code. It is > recognized by Clang, GCC, ICC. It will be compiled down to a single > instruction on platforms like IA-32. I can find the mailing list > messages for a citation, if needed. Cleared on the bit rotate branch at https://github.com/noloader/gnulib/tree/bitrotate. The patch is attached. Jeff