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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: C wish list
Date: Thu, 21 Mar 2019 12:43:40 -0700
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Howard Chu <highlandsun@gmail.com> writes:
[...]
> This is already a problem with the current syntax. CPUs don't have
> *signed integers*, they have *integers*. They have signed or unsigned
> *operators* for performing arithmetic on them - e.g. x86 MUL for
> unsigned multiplication, IMUL for signed multiplication. They have a
> single left-shift instruction because left-shift makes no difference
> whether you're doing signed or unsigned math. They have two
> right-shift instructions, one which shifts in 0 bits at the top, and
> one which shifts in copies of the sign bit at the top. But the sign
> bit isn't "special", it doesn't live in a separate memory or register
> space. It is merely the top-most bit of the word. They don't have
> signed vs unsigned Add or Subtract instructions because there is no
> difference.

None of this is a "problem".  C is not a high-level assembly language.
And not all CPUs have the characteristics you describe.

> For a language that evolved from PDP-11 assembly language, it has
> strayed pretty far from its roots. Words in a computer memory don't
> have types. They're just bytes; they're just sequences of bits. The
> only things that have "types" are the instructions that operate on
> them.

C did not evolve from PDP-11 assembly language.  It evolved from B,
which evolved from BCPL, which evolved from CPL, which was implemented
before the PDP-11 existed.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Will write code for food.
void Void(void) { Void(); } /* The recursive call of the void */