diff --git a/jaxlib/mosaic/dialect/tpu/transforms/infer_vector_layout.cc b/jaxlib/mosaic/dialect/tpu/transforms/infer_vector_layout.cc
index 25e50985864b..a4470efe8138 100644
--- a/jaxlib/mosaic/dialect/tpu/transforms/infer_vector_layout.cc
+++ b/jaxlib/mosaic/dialect/tpu/transforms/infer_vector_layout.cc
@@ -435,6 +435,7 @@ class VectorLayoutInferer {
       setLayout(op, src_layout, dst_layout);
       return success();
     }
+    op.emitOpError("unsupported truncation layout");
     return failure();
   }
 
@@ -494,6 +495,7 @@ class VectorLayoutInferer {
       setLayout(op, src_layout, dst_layout);
       return success();
     }
+    op.emitOpError("unsupported truncation layout");
     return failure();
   }