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From: black@ee.UCLA.EDU
Newsgroups: comp.unix.questions
Subject: Re: Evaluating autoincrements in function calls
Message-ID: <4715@brl-adm.ARPA>
Date: Thu, 26-Feb-87 19:47:33 EST
Article-I.D.: brl-adm.4715
Posted: Thu Feb 26 19:47:33 1987
Date-Received: Sat, 28-Feb-87 06:56:19 EST
Sender: news@brl-adm.ARPA
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> numbers in set indexed by incr integer = 3,2,1
> numbers in set indexed by constants = 1,2,3

I recall having this happen once.  Actually, it never 'happened';
I caught it before it was a bug (in the larval stage, one could say :=)).
A pass from lint caught it and said, "Order of evaluation unspecified."

If you look at "The Bible" (K&R C), page 192, you will see that
the comma operator does not really apply to this case.  Furthermore,
K&R, page 50, states a case almost exactly like yours and concludes:
"...writing code which depends on order of evaluation is bad..."

Caveat hacker!

Rex Black

black@ee.ucla.edu                                          ARPA        
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