Bug 16568 - MCS unexpected "is defined multiple times" error related to "Microsoft.VisualStudio.Shell.Interop"
Summary: MCS unexpected "is defined multiple times" error related to "Microsoft.Visual...
Status: NEW
Alias: None
Product: Compilers
Classification: Mono
Component: C# ()
Version: unspecified
Hardware: PC Windows
: --- normal
Target Milestone: ---
Assignee: Marek Safar
Depends on:
Reported: 2013-12-03 12:55 UTC by Brett van Swelm
Modified: 2013-12-06 08:43 UTC (History)
1 user (show)

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

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Description Brett van Swelm 2013-12-03 12:55:21 UTC
For this reproducer I used the Microsoft.VisualStudio.Shell.12.0.dll and Microsoft.VisualStudio.Shell.Interop.12.0.dll assemblies found here: https://github.com/jaredpar/VsVim/blob/master/References/Vs2013/Microsoft.VisualStudio.Shell.Interop.12.0.dll

With "D:\Applications\Mono-3.0.9\bin" and
"C:\Windows\Microsoft.NET\Framework\v4.0.30319" in the path on my Windows 7

===== Test.cs =====
class X {
    System.Type c = typeof(Microsoft.VisualStudio.Shell.Interop._VSRDTFLAGS4);
===== end =====

$ csc /target:library /r:Microsoft.VisualStudio.Shell.12.0.dll /r:Microsoft.VisualStudio.Shell.Interop.12.0.dll Test.cs
Microsoft (R) Visual C# Compiler version 4.0.30319.18408
for Microsoft (R) .NET Framework 4.5
Copyright (C) Microsoft Corporation. All rights reserved.

$ mcs /target:library /r:Microsoft.VisualStudio.Shell.12.0.dll /r:Microsoft.VisualStudio.Shell.Interop.12.0.dll Test.cs
Test.cs(2,65): error CS0433: The imported type `Microsoft.VisualStudio.Shell.Interop._VSRDTFLAGS4' is defined multiple times
C:\work\testing\simple\Microsoft.VisualStudio.Shell.12.0.dll (Location of the symbol related to previous error)
C:\work\testing\simple\Microsoft.VisualStudio.Shell.Interop.12.0.dll (Location of the symbol related to previous error)
Compilation failed: 1 error(s), 0 warnings


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Comment 1 Marek Safar 2013-12-06 08:42:54 UTC
This is noPIA feature. One of the types is  embedded interop type. We don't support noPIA yet