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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: Regarding assignment to struct
Date: Mon, 05 May 2025 21:25:16 -0700
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Michael S <already5chosen@yahoo.com> writes:

> On Sat, 3 May 2025 21:42:37 -0400
> Richard Damon <richard@damon-family.org> wrote:
>
>> Bigger than that, and you likely want to pass the object by address,
>> not by value, passing just a pointer to it.
>
> That sort of thinking is an example of Knutian premature optimization.

I don't agree with this assessment.  First, the given suggestion is
a rule of thumb.  By their nature rules of thumb offer heuristics
that give guidelines likely to yield good results, but not
guaranteed to do so.  Second, a decision about whether to pass a
struct object or a pointer to said object is often one that is a
fair amount of work to undo, and so tends to be made early during
the time period of program development.  As such, it is useful to
follow a guideline likely to give good results, even if not always
optimal, because on average it will mean less work done overall.

I second Richard Damon's recommendation, with the understanding that
it is only a guideline, not an absolute, and as always subject to
later revision should that turn out to be called for (no pun
intended).