fn __memset_chk(dest: ?[*]u8, c: c_int, n: usize, dest_n: usize) callconv(.c) ?[*]u8
fn __memset_chk(dest: ?[*]u8, c: c_int, n: usize, dest_n: usize) callconv(.c) ?[*]u8 { if (dest_n < n) __chk_fail(); return memset(dest, c, n); }