>No, the link errors are for __ctzdi2, not __clzdi2. >__ctzdi2 can be implemented using __ffs(). >> How's about we stop using __builtin_ctz[ll]() altogether? Use N-fls()? > >That was my first suggestion ;-) > Do we remove existing __builtin_ct[l]z? Some architecture's __builtin_clz will be more optimized than N-fls IMHO, This is not only about __builtin- but also supporting another libgcc functions in kernel. Some future user may need __clz[t]s[d]i2 symbol also. >> btw, this: >> >> int __weak __clzsi2(int val) >> { >> return BITS_PER_LONG - fls(val); >> } >> >> looks wrong. It will give a different result for 32- and 64-bit. > >Indeed. It should be hardcoded 32. > I will re-work this for 64-bit, and ctz also. Thanks Chanho Min -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html