Path: utzoo!mnetor!uunet!seismo!sundc!pitstop!sun!gorodish!guy
From: guy@gorodish.Sun.COM (Guy Harris)
Newsgroups: comp.lang.c
Subject: Re: volatile isn't necessary, but it's there
Message-ID: <49680@sun.uucp>
Date: 15 Apr 88 18:30:49 GMT
References: <7794@alice.UUCP> <48767@sun.uucp> <144@obie.UUCP>
Sender: news@sun.uucp
Lines: 28

>     /\              -  "Against Stupidity,  -    {backbones}!
>    /\/\  .    /\    -  The Gods Themselves  -  utah-cs!utah-gr!
>   /    \/ \/\/  \   -   Contend in Vain."   -  uplherc!sp7040!
>  / U i n T e c h \  -       Schiller        -     obie!wes

I guess Schiller is saying here that I'm wasting my time replying to this
article, but:

> Another good reason NOT to use a SPARC for anything other than a
> paperweight.  On a reasonable processor like the M68000, `++mutex'
> becomes an atomic operation like `addq	#1,mutex'.

Well, there would appear to be a hell of a lot of "unreasonable" processors
out there, such as most RISC machines, since they tend to be load/store
architectures with only register-to-register arithmetic.  You can stick with
your 68K if you wish; I suspect most people will be as happy, if not more
happy, with R2000s/R3000s, SPARCs, etc., etc. - or, for that matter, IBM 370s,
etc., etc., etc..

"++" isn't guaranteed to be atomic.  Period.  End of discussion.  The people at
e.g. MIPS and Sun seem to be able to deal with this; if you can't, that's your
problem.

> Did you get these bugs squashed, or will you relase the Sun-4 SunOS
> with them intact?

We fixed all the ones we ran into; none of those are in the first customer ship
version of Sys4-3.2L.