__builtin_ffsとはなにか？Other Builtins - Using the GNU Compiler Collection (GCC) http://gcc.gnu.org/onlinedocs/gcc-4.1.2/gcc/Other-Builtins.html によると Returns one plus the index of the least significant 1-bit of x, or if x is zero, ret…

__builtin_ffsはどこへ行くのか？