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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: A thought of C
Date: Thu, 23 Apr 2026 08:07:45 -0700
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Michael S <already5chosen@yahoo.com> writes:

[.. discussing a code transformation..]

> Indeed, transformation applied by compilers in this case is
> more complex than mere [tail call elimination].
>
> In theory, it can be a result of two successive transformations.
> First transforming original to fib2:
>
> unsigned long long fib2(unsigned long long n, unsigned long long acc)
> {
>   if (n < 3)
>     return acc + 1;
>   return fib2(n-2, fib2(n-1, acc));
> }
>
> Ant then applying TCE.
> But more likely compiler arrived to the same outcome by different
> logical steps.

I have long since given up trying to guess how a compiler arrives
at an ultimate fomulation of what code to produce.  And it is
surely only going to be harder to divine such results in the
future.