https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115019
--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #2)
> /app/example.cpp:36:24: runtime error: negation of
> 0x80000000000000000000000000000000 cannot be represented in type '__int128';
> cast to an unsigned type to negate this value to itself
Once I fix that with:
```
static char *itoa128(char *buf, __int128_t v)
{
if (v < 0) {
buf = utoa128(buf, -(__uint128_t)v);
```
GCC behavior is what you expect.
