Path: utzoo!mnetor!uunet!husc6!purdue!i.cc.purdue.edu!j.cc.purdue.edu!ksb
From: ksb@j.cc.purdue.edu (Kevin Braunsdorf)
Newsgroups: comp.lang.c
Subject: unions and volatile qualifiers
Message-ID: <6891@j.cc.purdue.edu>
Date: 9 Apr 88 18:26:15 GMT
References: <12578@brl-adm.ARPA>
Reply-To: ksb@j.cc.purdue.edu.UUCP (Kevin Braunsdorf)
Distribution: na
Organization: K Project
Lines: 27
Keywords: volatile and the union

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All the members of this union should be tagged as being volatile.

	union {
		int oi;
		char oc;
	} u;
	int *pi;

	pi = & u.oi;			/* should be a comment || warning */

You see why they cannot be ordinary in the union?

Another case:
	union {
		noalias int ei;		/* should be a comment || warning */
		char oops;
	} u2;

the int is not exclusive in the union, it cannot be.

Do we all agree that a volatile is needed here (in unions)?

I'll discuss this through mail with anyone who cares.

kayessbee		pur-ee!ksb	ksb@j.cc.purdue.edu