Re:Xcode 4 ships a buggy compiler
by bdonlan on Saturday December 31, 2011 @09:49AM
(#3410951)
The 'consistency' I speak of is the idea that, if I assign alloca(0) to a variable, it's either NULL or non-NULL - I can't look at that same variable two different ways and get different answers. From the sounds of the article, this requirement might be violated by this bug.
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I don't think so. Only one comparison is being done in the example code. I'd bet that if you e.g. printed out the value of the pointer before the if statement, the optimization would no longer kick in as it does.