conditional expression evaluation question

[Mark Nagel]

The original question regarded the evaluation of a bitwise or expression
which would *always* be fully evaluated.  C only guarantees that logical
expressions will be short circuited.  There may be a problem with your
expression though in other ways.  C does not guarantee that an expression
with side effects will be executed in any special order.  Therefore, the
original expression:

	if (*cp++ | *cp++ | *cp++ == 0) {
	    ...
	}

will evaluate each *cp++ eventually, but I do not believe you can assume
the result will be the same as (*cp | *(cp+1) | *(cp+2)) followed by
cp += 3 on all machines.


- Mark Nagel

ucdavis!deneb!cccmark at ucbvax.berkeley.edu               (ARPA)
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