编译.net core cli的源码出错

悬赏园豆：20 [待解决问题]

从github上签出.net core cli的源代码，在windows上运行build.cmd，运行过程中出现如下的错误：

C:\Dev\GitHub\cli\.nuget\packages\microsoft.net.sdk\1.0.0-alpha-20161104-2\build
\Microsoft.NET.RuntimeIdentifierInference.targets(45,5): error : RuntimeIdentifi
er must be set for .NETFramework executables. Consider RuntimeIdentifier=win7-x8
6 or RuntimeIdentifier=win7-x64. [C:\Dev\GitHub\cli\TestAssets\TestPackages\dotn
et-desktop-binding-redirects\dotnet-desktop-binding-redirects.csproj] [C:\Dev\Gi
tHub\cli\build.proj]
Failed to build
At C:\Dev\GitHub\cli\run-build.ps1:122 char:31
+     if($LASTEXITCODE -ne 0) { throw "Failed to build" }
+                               ~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : OperationStopped: (Failed to build:String) [], R
   untimeException
    + FullyQualifiedErrorId : Failed to build

请问如何解决这个问题？

.net core