How to GetSemanticModel for any syntax tree in referenced projects of project compilation
<p>When I compile a project (using <code>MSBuildWorkspace.Create().OpenProjectAsync().GetCompilationAsync();</code> I get a <code>Compilation</code> back which includes <em>x</em> SyntaxTrees for the <em>x</em> files within that project. But that project also references other projects. I can see the those projects within the <code>References</code> property of the <code>Compilation</code>, but it seems that calling <code>Compliation.GetSemanticModel</code> does not look through these.</p>

<p>For an arbitrary <code>SyntaxTree</code> that is <em>somewhere</em> within my project (including referenced projects) do I have to manually search through each referenced <code>Compilation</code> of the root project or is there are helper method or some other approach to this?</p>