Path: utzoo!utgpu!water!watmath!clyde!cbosgd!ihnp4!ihlpf!nevin1
From: nevin1@ihlpf.ATT.COM (00704A-Liber)
Newsgroups: comp.lang.c
Subject: Re: noalias and vectors
Keywords: noalias, auto-vectorizing
Message-ID: <3419@ihlpf.ATT.COM>
Date: 19 Jan 88 02:24:28 GMT
References: <2942@hall.cray.com> <531@cresswell.quintus.UUCP> <7088@brl-smoke.ARPA>
Reply-To: nevin1@ihlpf.UUCP (00704A-Liber,N.)
Organization: AT&T Bell Laboratories - Naperville, Illinois
Lines: 16

In article <7088@brl-smoke.ARPA> gwyn@brl.arpa (Doug Gwyn (VLD/VMB) <gwyn>) writes:
>The appearance of "noalias" in interface specifications is a powerful
>aid.  It lets you know that a function is not designed to be safely
>used in alias situations.  For example, it warns that strcpy() must
>not be used to copy a string into an overlapping portion of the same
>char array.

Actually, from what I understand, all that noalias would mean here is that s1
and s2 don't point to EXACTLY the same place (although in most situations the
compiler cannot enforce this restriction till run-time).  Overlap would still
be allowed.  (BTW, strcpy() WILL work in most implementations if s1 == s2.)
-- 
 _ __			NEVIN J. LIBER	..!ihnp4!ihlpf!nevin1	(312) 510-6194
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