ALT_FLAGS_SHIFT
#define ALT_NOT(feature) ((ALT_FLAG_NOT << ALT_FLAGS_SHIFT) | (feature))
#define ALT_DIRECT_CALL(feature) ((ALT_FLAG_DIRECT_CALL << ALT_FLAGS_SHIFT) | (feature))
#define ALT_FEATURE_MASK ((1 << ALT_FLAGS_SHIFT) - 1)
return (ft_flags >> ALT_FLAGS_SHIFT);