everyone! First post.
I have this very simple material node setup which both displays in Viewport Shading mode and renders in Eevee perfectly fine with no problem. In Cycles, however, all I get is a black silhouette.
The culprit appears to be the Attribute node at the end, which is feeding the Vector property into a simple Checker Texture. I kept the scene minimal so that the screenshots plainly lay out everything happening in both the Shader Editor and the Outliner (i.e., hardly anything) for you to see.
I need this mapping setup in order to dynamically texture a revolve/lathe surface built with the Screw modifier applied to a curve, as shown in the top screenshot pair.
For simplicity, however, further down below, I've included another pair of screenshots that illustrate the same issue using the default Torus primitive.