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From: Keith Thompson <Keith.S.Thompson+u@gmail.com>
Newsgroups: comp.lang.c
Subject: Re: Regarding assignment to struct
Date: Mon, 05 May 2025 17:53:14 -0700
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Tim Rentsch <tr.17687@z991.linuxsc.com> writes:
> Keith Thompson <Keith.S.Thompson+u@gmail.com> writes:
>> Andrey Tarasevich <noone@noone.net> writes:
>> [...]
>>
>>>   #include <stdio.h>
>>>
>>>   struct S { int a[10]; };
>>>
>>>   int main()
>>>   {
>>>     struct S a, b = { 0 };
>>>     int *pa, *pb, *pc;
>>>
>>>     pa = &a.a[5],
>>>     pb = &b.a[5],
>>>     pc = &(a = b).a[5],
>>>     printf("%p %p %p\n", (void *) pa, (void *) pb, (void *) pc);
>>>   }
>>>
>>> This version has no UB.
>>
>> I believe it does.  [...]
>
> If you look again carefully, I expect you will reach a
> different conclusion.

Please explain.  Or don't.

I explained, in text that you snipped, why I think it has UB.
If there's a flaw in my reasoning, I invite you to point it out
without being mysterious.

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
void Void(void) { Void(); } /* The recursive call of the void */