Bug 56750 - System.ValueType no longer working for iOS
Summary: System.ValueType no longer working for iOS
Status: RESOLVED DUPLICATE of bug 56457
Alias: None
Product: Visual Studio Extensions
Classification: Xamarin
Component: iOS ()
Version: unspecified
Hardware: PC Windows
: --- normal
Target Milestone: 15.2.2
Assignee: Bugzilla
Depends on:
Reported: 2017-05-23 08:13 UTC by jeroen.bernsen
Modified: 2017-06-07 20:57 UTC (History)
6 users (show)

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

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Description jeroen.bernsen 2017-05-23 08:13:45 UTC
After switching to a new Windows PC I keep getting these iOS build errors during compilation:

error CS8137: Cannot define a class or member that utilizes tuples because the compiler required type 'System.Runtime.CompilerServices.TupleElementNamesAttribute' cannot be found. Are you missing a reference?
error CS8179: Predefined type 'System.ValueTuple`2' is not defined or imported

Installing package System.ValueTuple does not help.

See also: https://developercommunity.visualstudio.com/content/problem/55133/xamarinios-cannot-resolve-systemvaluetuple.html

Problem is fixed after manually adding this reference: nuget\packages\system.valuetuple\4.3.1\lib\portable-net40+sl4+win8+wp8

This should not be necessary!
Comment 1 jeroen.bernsen 2017-05-24 10:16:18 UTC
Some new info on the bug:
On my desktop PC (VS2017 Enterprise) I need to remove the reference otherwise it won't compile. 
On my laptop (VS2017 Pro) I need to add the reference otherwise it won't compile.

In both cases same errors about Tuples.

Both running Xamarin iOS v10.10.0.30.
Comment 2 Emanuel 2017-06-07 20:57:41 UTC

*** This bug has been marked as a duplicate of bug 56457 ***