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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: What is your opinion about unsigned int u = -2 ?
Date: Sun, 11 Aug 2024 13:57:07 -0700
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Keith Thompson <Keith.S.Thompson+u@gmail.com> writes:

> Thiago Adams <thiago.adams@gmail.com> writes:
>
>> More samples..
>> max uint64  + 1 is signed 128 bits in gcc and unsigned  long long in clang
>>
>> #ifdef __clang__
>> static_assert(TYPE_IS(9223372036854775808, unsigned long long ));
>> #else
>> static_assert(TYPE_IS(9223372036854775808, __int128));
>> #endif
>>
>> https://godbolt.org/z/hveY44ov4
>
> 9223372036854775808 is 2**63, or INT64_MAX-1, not UINT64_MAX-1.

Of course you meant INT64_MAX + 1 (and presumably UINT64_MAX + 1).