10c9eea8f9
commit 9f1d62bed7 upstream.
This is because __builtin_clz(0) returns 64 for the "undefined" case
of 0, since the builtin just does a right-shift 32 and "clz" instruction.
So, use the alpha approach of casting to u32 and using __builtin_clzll().
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>