Re: Code Warrior compiler optimizations causing bug.

[Ben Combee]

At 00:00 2002-11-16 +0100, you wrote:

On Fri, Nov 15, 2002 at 04:28:26PM -0600, Ben Combee wrote:
>>> [...] RecordSize+=(len=StrLen(Data.Field2))+((len>0)?1:0);
>
> The only C/C++ operators that have an implied order are the shortcut
> evaluation operators || and &&.

And also ?: and , and several other (non-operator) contexts.
The buzzword to look for in the standards, FAQs, and newsgroups is
"sequence point".

Right... I was thinking binary operators -- <foo> ? <bar> : <baz> does have embedded sequence points.

Me, I didn't think the bad programming practice in the original code was
the use of the ?: operator, but rather the way the code is all scrunched
together instead of spelling out what it's really doing.  Compare

        if ((len = StrLen (Data.Field2)) > 0)  RecordSize += len + 1;

which doesn't contain a sequence point violation.  That's not a
coincidence :-).  (Yes, I realise some would prefer to see it written
out even more verbosely.)

Much improved style in your reformulation, although I'd probably cringe a little at the embedded assignment in the if, as my spidey-sense would go off at seeing a single '=' in an if expression.

--
Ben Combee <[EMAIL PROTECTED]>
CodeWarrior for Palm OS technical lead
Palm OS programming help @ www.palmoswerks.com


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