a_ctz_32
#define a_ctz_32 a_ctz_32
#define a_ctz_32 a_ctz_32
#ifndef a_ctz_32
#define a_ctz_32 a_ctz_32
return 32 + a_ctz_32(y);
return a_ctz_32(y);
return (sizeof(long) < 8) ? a_ctz_32(x) : a_ctz_64(x);
return 31-a_ctz_32(x);