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copied!<p>As the other poster pointed out, you are returning a CGPath reference taken from a UIBezierPath object that goes out of scope at the end of the method. As the docs on the UIBezierPath CGPath property say:</p> <blockquote> <p>The path object itself is owned by the UIBezierPath object and is valid only until you make further modifications to the path.</p> </blockquote> <p>You need to create a copy of your CGPath and return that:</p> <pre><code>-(CGPathRef)makeToPath { UIBezierPath* triangle = [UIBezierPath bezierPath]; [triangle moveToPoint:CGPointZero]; [triangle addLineToPoint:CGPointMake(self.view.frame.size.width,0)]; [triangle addLineToPoint:CGPointMake(0, self.view.frame.size.height)]; [triangle closePath]; CGPathRef theCGPath = [triangle CGPath]; return CGPathCreateCopy(theCGPath); } </code></pre> <p>The way I read the link to the llvm project, I think that the cf_returns_retained qualifier is intended to tell the caller the memory management policy for the returned value, rather than doing the retain for you. </p> <p>Thus I think you would both need to create a copy of the path AND add the cf_returns_retained qualifier. I'm not clear on the syntax of that qualifier, however. (Never used it before.)</p> <p>Assuming the other poster had the right syntax, it would look something like this:</p> <pre><code>-(CGPathRef)makeToPath CF_RETURNS_RETAINED; { UIBezierPath* triangle = [UIBezierPath bezierPath]; [triangle moveToPoint:CGPointZero]; [triangle addLineToPoint:CGPointMake(self.view.frame.size.width,0)]; [triangle addLineToPoint:CGPointMake(0, self.view.frame.size.height)]; [triangle closePath]; CGPathRef theCGPath = [triangle CGPath]; return CGPathCreateCopy(theCGPath); } </code></pre>

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