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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: Safety of casting from 'long' to 'int'
Date: Tue, 12 May 2026 19:02:42 -0700
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scott@slp53.sl.home (Scott Lurndal) writes:

> For the early C compiler on the PDP-11, the 'int' type was
> 16-bits, implicitly signed, and the code generator simply emitted
> available arithmetic instructions.
>
> It was the only C compiler at the time, any guarantees would have
> been implicit in the choice of target architecture.
>
> I mostly wrote unix kernel code using the v6 compiler, rather than
> writing code that did any heavy math, so whether value was
> preserved or sign was preserved wasn't something I, as a kernel
> programmer, routinely considered.

If int was only 16 bits, I expect promotion considerations didn't
come up very often.