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F# Project Reference issue on netcore 2.0

See original GitHub issue

The following F# project works fine when TargetFramework is netstandard1.6 / netcoreapp1.0 but fails with netstandard2.0 / netcoreapp2.0 (but same project works on 2.0 if --language is C#).

Steps to reproduce

/test/lib/lib.fsproj:

<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <TargetFramework>netstandard2.0</TargetFramework>
  </PropertyGroup>
  <ItemGroup>
    <Compile Remove="**/*.fs" />
    <Compile Include="Library.fs" />
  </ItemGroup>
</Project>

/test/app/app.fsproj:

<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>netcoreapp2.0</TargetFramework>
  </PropertyGroup>
  <ItemGroup>
    <ProjectReference Include="../lib/lib.fsproj" />
  </ItemGroup>
  <ItemGroup>
    <Compile Remove="**/*.fs" />
    <Compile Include="Program.fs" />
  </ItemGroup>
</Project>

/test/lib/Library.fs:

namespace Lib
module Say =
    let hello name = printfn "Hello World from %s!" name

/test/app/Program.fs:

[<EntryPoint>]
let main argv =
    Lib.Say.hello "F#"
    0

Expected behavior

Hello World from F#!

Actual behavior

Unhandled Exception: System.MissingMethodException: Method not found: 'Void Lib.Say.hello(System.String)'.
   at Program.main(String[] argv)

Environment data

dotnet --info output:

.NET Command Line Tools (2.1.0-preview1-006474)

Product Information:
 Version:            2.1.0-preview1-006474
 Commit SHA-1 hash:  e3d388e82d

Runtime Environment:
 OS Name:     Windows
 OS Version:  10.0.14393
 OS Platform: Windows
 RID:         win10-x64
 Base Path:   C:\Program Files\dotnet\sdk\2.1.0-preview1-006474\

Microsoft .NET Core Shared Framework Host

  Version  : 2.0.0-preview2-25407-01
  Build    : 40c565230930ead58a50719c0ec799df77bddee9