fn __memcpy_chk(noalias dest: ?[*]u8, noalias src: ?[*]const u8, n: usize, dest_n: usize) callconv(.c) ?[*]u8
fn __memcpy_chk(noalias dest: ?[*]u8, noalias src: ?[*]const u8, n: usize, dest_n: usize) callconv(.c) ?[*]u8 { if (dest_n < n) __chk_fail(); return memcpy(dest, src, n); }