Cannot remove a reference in Visual Studio 2013

Question

I am building ironpython3 with Visual Studio 2013. In the references Visual Studio shows a yellow triangle on Microsoft.Scripting.Core reference. Since I read this reference has been moved to System.Core I simply removed the reference to Microsoft.Scripting.Core. The project builds just fine without this reference. But after ending Visual Studio and opening the project again, the reference is just back. I removed all references I found (Strg-Shift-F) from the sources, but still no change. I had a look in the .csproj file but did not find any references there. I simply cannot remove the reference permanently. Any ideas where to look to permanently remove the reference? Thank you.

Answer 1

As Pawel said, IronPython uses a complex build system to handle all of the platforms it supports and make it easy-ish to add new ones (at least until IronPython and the DLR can be refactored into portable libraries ... sometime around 2016). In this case you need to dig through a couple of levels of imports to find where it's defined (Build/Common.proj).

The reason this happen is that even though the Reference is conditional (and handled correctly) in MSBuild, VS ignores the conditional check and displays any Reference elements it finds. Moving the Reference into Build/net35.props instead should fix the display, since VS does a much better job of handling imports.