[Bug middle-end/89977] missing -Wstringop-overflow with an out-of-bounds int128_t range

[JunMa at linux dot alibaba.com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89977

--- Comment #2 from JunMa <JunMa at linux dot alibaba.com> ---
After a bit more thinking, the behavior of gcc trunk is right. the range of n_3
in truncation from int128 to long unsigned int equal to the range of long
unsigned int. for example: if n_3 = 0x100000000, then _1 is 0 which is less
than 7.

so this is not a bug.