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dotnet build results in error CS0579 duplicate attributes with AssemblyVersionAttribute (and others) specified

See original GitHub issue

Building a library project fails with error CS0579 (duplicate attribute) with library projects with AssemblyVersionAttribute (or other assembly attributes) specified.

Adding (for example) <GenerateAssemblyVersionAttribute>false</GenerateAssemblyVersionAttribute> to csproj fixes

Steps to reproduce

dotnet new -t lib
insert [assembly: System.Reflection.AssemblyVersion("0.1.0.0")] into Library.cs
dotnet restore
dotnet build

Expected behavior

Build is successful

Actual behavior

Build fails:

   "C:\dsedev\src\AssemblyInfoTest\AssemblyInfoTest.csproj" (Build target) (1) ->
   (CoreCompile target) ->
     obj\Debug\netstandard1.4\AssemblyInfoTest.AssemblyInfo.cs(13,12): error CS0579: Duplicate 'System.Reflection.AssemblyVersionAttribute' attribute [C:\dsedev\src\AssemblyInfoTest\AssemblyInfoTest.csproj]

Environment data

C:\dsedev\src\AssemblyInfoTest>dotnet --info
.NET Command Line Tools (1.0.0-preview3-004056)

Product Information:
 Version:            1.0.0-preview3-004056
 Commit SHA-1 hash:  ccc4968bc3

Runtime Environment:
 OS Name:     Windows
 OS Version:  10.0.14393
 OS Platform: Windows
 RID:         win10-x64

Issue Analytics

State:
Created 7 years ago
Reactions:3
Comments:14 (4 by maintainers)

Top GitHub Comments

54reactions

frankbuckleycommented, Nov 19, 2016

Setting GenerateAssemblyInfo property to false fixes for all attributes:

<PropertyGroup>
  <GenerateAssemblyInfo>false</GenerateAssemblyInfo>
</PropertyGroup>

5reactions

alexelliscommented, Aug 16, 2017

This is a very odd error and unexpected - I got it by creating a new “console” type of project, a “library” type and then referencing the library from the console app.

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