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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: Regarding assignment to struct
Date: Sun, 04 May 2025 06:48:13 -0700
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Andrey Tarasevich <noone@noone.net> writes:

> On Fri 5/2/2025 11:34 AM, Lew Pitcher wrote:
>
>> Back in the days of K&R, Kernighan and Ritchie published an addendum
>> to the "C Reference Manual" titled "Recent Changes to C" (November 1978)
>> in which they detailed some differences in the C language post "The
>> C Programming Language".
>>
>> The first difference they noted was that
>>    "Structures may be assigned, passed as arguments to functions, and
>>     returned by functions."
>>
>>  From what I can see of the ISO C standards, the current C language
>> has kept these these features.  However, I don't see many C projects
>> using them.
>
> Weird.  Virtually every C project relies on assignment of
> structures.  Passing-returning structs by value might be more rare
> (although perfectly valid and often appropriate too), but
> assignment... assignment is used by everyone everywhere without even
> giving it a second thought.
>
> One dark corner this feature has, is that in C (as opposed to C++) the
> result of an assignment operator is an rvalue, which can easily lead
> to some interesting consequences related to structs with arrays
> inside.

I'm curious to know what interesting consequences you mean here.  Do
you mean something other than cases that have undefined behavior?