message: try to fix macos build..
diff: using namespace std;
  +#if defined(__clang__) && __clang_major__ < 13 && defined(__apple_build_version__)
  +namespace {
  +bool has_single_bit(uint64_t n) {
  + return n != 0 && (n & (n - 1)) == 0;
  +}
  +
  +unsigned bit_width(uint64_t n) {
  + return 64 - countl_zero(n);
  +}
  +}
  +#endif
  +
  namespace util {
  unsigned ilog2(uint64_t n) {
  @@ -28,7 +40,7 @@ bool is_power2(uint64_t n, uint64_t *log) {
  }
  unsigned num_sign_bits(uint64_t n) {
  - return max(countl_zero(n), countl_one(n));
  + return max(countl_zero(n), countl_one(n)) -1;
  }
  uint64_t add_saturate(uint64_t a, uint64_t b) {
  