Created Unassigned: Build errors after view modifications [170]

Almost every time I modify a view, I see the errors below on build. If I delete the obj > CodeGen folder and rebuild, the error goes away. I'm using MVC 5.2.0.0.

Could not precompile the file '\Views\Shared\Licence\_Licence.cshtml'. Ensure that a generator declaration exists in the cshtml file
A generator declaration is the first line of your cshtml file and looks like this:
@* Generator: MvcHelper *@
Valid host names: MvcHelper, MvcView, Template, WebPagesHelper, WebPage, RazorGenerator.Core.IHostProvider