Path: utzoo!mnetor!uunet!pwcmrd!skipnyc!atpal!tneff
From: tneff@atpal.UUCP (Tom Neff)
Newsgroups: comp.lang.c
Subject: Re: volatile, noalias and optimization
Message-ID: <135@atpal.UUCP>
Date: 27 Apr 88 15:23:57 GMT
References: <20345@pyramid.pyramid.com> <132@atpal.UUCP> <3637@haddock.ISC.COM>
Reply-To: tneff@atpal.UUCP (Tom Neff)
Organization: Rational Technologies, Inc.
Lines: 21
Summary: Score one for the Walking Lint

In article <3637@haddock.ISC.COM> karl@haddock.ima.isc.com (Karl Heuer) asks:
>In article <132@atpal.UUCP> uunet!pwcmrd!skipnyc!atpal!tneff (Tom Neff) writes:
>>This is a wonderful feature ... but shouldn't we use
>>        #pragma volatile(var1, var2, var3)
>>instead of imposing a new keyword on the language grammar?
>
>Unless you expand on this a bit, it's not as powerful.  I've actually used the
>declaration "char volatile * volatile p;" (a volatile pointer to volatile
>memory) -- would your proposal handle this?

You're right, Karl, the #pragma approach wouldn't work for nested volatile
references like your example, and I can't think of a graceful way to extend
my proposal to deal with it either.  I guess, then, that the compelling 
argument for extending the name space to include volatile is that it needs
syntactic access to the declarations themselves.  Thanks for pointing this
out!  (It's amazing how sweet tempered one feels on reading of noalias's 
demise...)
-- 
Tom Neff			UUCP: ...uunet!pwcmrd!skipnyc!atpal!tneff
	"None of your toys	CIS: 76556,2536		MCI: TNEFF
	 will function..."	GEnie: TOMNEFF		BIX: are you kidding?