Bug 27439 - Null values seem to not be getting caught by a null check and allowed to continue execution
Summary: Null values seem to not be getting caught by a null check and allowed to cont...
Status: RESOLVED NORESPONSE
Alias: None
Product: iOS
Classification: Xamarin
Component: XI runtime ()
Version: master
Hardware: PC Mac OS
: Normal normal
Target Milestone: Untriaged
Assignee: Bugzilla
URL:
Depends on:
Blocks:
 
Reported: 2015-02-25 18:30 UTC by Rob DeRosa
Modified: 2016-05-26 21:35 UTC (History)
3 users (show)

Tags:
Is this bug a regression?: ---
Last known good build:


Attachments
Screenshot (123.71 KB, image/png)
2015-02-25 18:30 UTC, Rob DeRosa
Details


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Status:
RESOLVED NORESPONSE

Description Rob DeRosa 2015-02-25 18:30:39 UTC
Created attachment 10038 [details]
Screenshot

A variable that has been assigned a null value seems to pass through certain lines of code unfettered yet other lines of code throw the correct NullObjRef exception. In this case, bad JSON serialization results in a null value for a variable. According to the screenshot, the null exception should have been thrown on line 77 and the 'continue' statement on line 83 should have caused the execution to move along.

I could probably put together a sample project if that would be helpful.


================================

=== Xamarin Studio ===

Version 5.7.1 (build 17)
Installation UUID: bdf70f16-1419-4199-bea0-587898533ffe
Runtime:
	Mono 3.12.0 ((detached/de2f33f)
	GTK+ 2.24.23 (Raleigh theme)

	Package version: 312000076

=== Xamarin.Android ===

Version: 4.20.0.28 (Enterprise Edition)
Android SDK: /Volumes/Documents/Rob/Library/Developer/Xamarin/android-sdk-macosx
	Supported Android versions:
		2.1   (API level 7)
		2.2   (API level 8)
		2.3   (API level 10)
		3.1   (API level 12)
		4.0.3 (API level 15)
		4.1   (API level 16)
		4.2   (API level 17)
		4.3   (API level 18)
		4.4   (API level 19)
		5.0   (API level 21)
Java SDK: /usr
java version "1.6.0_65"
Java(TM) SE Runtime Environment (build 1.6.0_65-b14-466.1-11M4716)
Java HotSpot(TM) 64-Bit Server VM (build 20.65-b04-466.1, mixed mode)

=== Apple Developer Tools ===

Xcode 6.1.1 (6611)
Build 6A2008a

=== Xamarin.iOS ===

Version: 8.6.1.26 (Enterprise Edition)
Hash: 98ee412
Branch: 
Build date: 2015-02-11 04:37:05-0500

=== Xamarin.Mac ===

Version: 1.12.0.8 (Enterprise Edition)

=== Build Information ===

Release ID: 507010017
Git revision: 0bc7d3550b6b088ac25b08dcf7bbe73bcc8658b3
Build date: 2015-02-03 19:43:29-05
Xamarin addins: f7b7d34419c9ec24501bfa7c658e80a6305613e0

=== Operating System ===

Mac OS X 10.10.2
Darwin Robs-iMac-2.local 14.1.0 Darwin Kernel Version 14.1.0
    Mon Dec 22 23:10:38 PST 2014
    root:xnu-2782.10.72~2/RELEASE_X86_64 x86_64
Comment 1 Sebastien Pouliot 2015-02-25 22:18:39 UTC
It could be many things:

1. a threading issue (`s` was not null earlier); 

or

2. an extension method (which can accept a null `this` argument). It's not the case here as it's a property (and there's no extension properties, still it's a surprising debugging experience when it happens ;-)

or

3. the debugger being out-of-sync (and not showing you the right value). 

Hard to say... a test case is needed.
Comment 2 Sebastien Pouliot 2016-05-26 21:35:19 UTC
We have not received the requested information. If you are still experiencing this issue please provide all the requested information and re-open the bug report. Thanks!