NSNumber initialization issue

Question

Recently I found interesting problem connected with NSNumber initialization.

The difference occurred between simulator (9.3.1) and device (9.3.1).

Let assume that we've got int x = 2; Now we're initializing NSNumber and passing it to a method.

NSNumber *test = [NSNumber numberWithInt:self.x];
[self.method setTestNumber: test];

This two lines had a correct result on both simulator and device.

BUT using only this line

[self.method setTestNumber:[NSNumber numberWithInt:self.x]];

had quite unexpected result. Running it on simulator NSNumber intValue was equal to 2.

Running it on device had incorrect random value. How is that possible? Device is iPad 4 A1458. Also tested on iPad 3 16GB. The same problem occurred. Can you verify this problem?

I can not reproduce your problem. It would be helpful to see how your "method" class looks like and how you initilize it. — tuvok, May 12 '16 at 12:55
write your `setTestNumber` method. Problem should be there in that method — Ketan Parmar, May 12 '16 at 13:34
What do you mean by "simulator (9.3.1)"? We haven't released an iOS 9.3.1 simulator runtime. I assume you mean with iOS 9.3? — Jeremy Huddleston Sequoia, May 12 '16 at 18:54
I can't post exactly this method because of NDA. Yes I mean simulator 9.3 my bad. — Piotr Gawłowski, May 13 '16 at 07:36

score 0 · Answer 1 · answered May 12 '16 at 18:55

0

The compiler will actually optimize those two codepaths to the exact same asm. There is no difference between them.

answered May 12 '16 at 18:55

Jeremy Huddleston Sequoia

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I will reproduce it later and post exact code/github repo + screenshots showing this effect on side-project. I can't post exact code now because of NDA. – Piotr Gawłowski May 13 '16 at 07:37

NSNumber initialization issue

1 Answers1