[swift-users] Debugger woes

Jim Ingham jingham at apple.com
Fri Feb 3 10:32:45 CST 2017


> On Feb 3, 2017, at 6:55 AM, Maury Markowitz <maury.markowitz at gmail.com> wrote:
> 
>> On Jan 31, 2017, at 1:59 PM, Jim Ingham <jingham at apple.com> wrote:
>> 
>> From the symptoms, it looks like the compiler is not holding onto "background" because it is no longer used.  That's a desirable thing to do for optimized code, but not at -O0.
>> 
>> What happens if you rewrite this to:
>> 
>> 		let background = sceneView.snapshot().cgImage!
>> 		let cropped = background.cropping(to: overlayView.frame)
>> 		UIGraphicsBeginImageContextWithOptions(overlayView.frame.size, false, 1.0)
>>               print(background)
> 
> I've been battling H3N2 so I only got a chance to try this now. Indeed, the 'background' variable is "alive" in this version, I assume because of the print() that follows?

Yes, that's most likely right.

> 
> Should I file through the normal Apple Bug Reporter, or is there a better mechanism for Swift-related issues?

The official word on that is:

https://swift.org/contributing/#reporting-bugs

Jim



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