Notice (2018-05-24): bugzilla.xamarin.com is now in
Please join us on
Visual Studio Developer Community and in the
Mono organizations on
GitHub to continue tracking issues. Bugzilla will remain
available for reference in read-only mode. We will continue to work
on open Bugzilla bugs, copy them to the new locations
as needed for follow-up, and add the new items under Related
Our sincere thanks to everyone who has contributed on this bug
tracker over the years. Thanks also for your understanding as we
make these adjustments and improvements for the future.
Please create a new report on
Developer Community or GitHub with
your current version information, steps to reproduce, and relevant error
messages or log files if you are hitting an issue that looks similar to
this resolved bug and you do not yet see a matching new report.
1. Create an iOS Project
2. Add this line of code in FinsishedLaunching or other method:
System.ComponentModel.CancelEventArgs cea = new System.ComponentModel.CancelEventArgs();
3. Build project
4. Project build succeeds.
5. Add a reference to OpenTK or OpenTK-1.0
6. Build project.
Expected result: build succeeds.
Actual result: build fails with Error CS0433: The imported type `System.ComponentModel.CancelEventArgs' is defined multiple times (CS0433) (totktest)
Might be good to note that This does not occur in a Xamarin.Android Application.
Checked, we are getting 'Error CS0433' when OpenTK or OpenTK-1.0 is referenced to iOS project.
Build Output: https://gist.github.com/saurabh360/97c7deaf9cb2d8fc339f
IDE Log: https://gist.github.com/saurabh360/3b47f31fb4aa69fb939e
Version 5.0 (build 878)
Installation UUID: 1151d3d9-29c1-4339-b53c-a54856b47901
Mono 3.4.0 ((no/c3fc3ba)
GTK+ 2.24.23 (Raleigh theme)
Package version: 304000204
Version: 4.12.4 (Enterprise Edition)
Android SDK: /Users/shruti/Desktop/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)
3.2 (API level 13)
4.0 (API level 14)
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)
Java SDK: /usr
java version "1.7.0_55"
Java(TM) SE Runtime Environment (build 1.7.0_55-b13)
Java HotSpot(TM) 64-Bit Server VM (build 24.55-b03, mixed mode)
Apple Developer Tools
Xcode 5.1 (5084)
Version: 126.96.36.199 (Enterprise Edition)
Build date: 2014-05-19 19:10:29-0400
Xamarin.Mac: Not Installed
Release ID: 500000878
Git revision: bcd66920d963483e7d638a2339c4022fe035b529
Build date: 2014-05-27 17:36:26-04
Xamarin addins: da9064ce55b0fa90930a7c437a4cc1ae0e5c778c
Mac OS X 10.9.2
Darwin Shrutis-Mac-mini.local 13.1.0 Darwin Kernel Version 13.1.0
Thu Jan 16 19:40:37 PST 2014
Look like old version of XI's System.dll did not have the type and it was added inside OpenTK.dll
The type was added to System.dll so it now conflicts. That's a breaking change to remove it - but there's not really an alternative.
Fixed in master 3ab7378d862c381b37d95809aa74013fd6cc77db
QA: unit test added in same revision