I am unable to build UE Github Master branch due to a missing function, UEditorEngine::UpdateShaderComplexityMaterials(). This function is called in EditorEngine.cpp on or around line 7411. Commenting out this line enables compilation to continue to success.
The master branch usually have incomplete code as Epic uses it for daily development, it’ll be probably fixed tomorrow anyways as soon as they run into it (or it might be already fixed in Perforce).