diff --git a/vmvx_ukernel/query_tile_sizes.c b/vmvx_ukernel/query_tile_sizes.c
index e3c9222..169cf9c 100644
--- a/vmvx_ukernel/query_tile_sizes.c
+++ b/vmvx_ukernel/query_tile_sizes.c
@@ -79,7 +79,7 @@
   }
 }
 
-IREE_UK_EXPORT void iree_uk_query_tile_sizes_2d(
+IREE_UK_EXPORT int iree_uk_query_tile_sizes_2d(
     const iree_uk_query_tile_sizes_2d_params_t* params,
     iree_uk_query_tile_sizes_2d_out_params_t* out_params) {
   iree_uk_query_tile_sizes_2d_validate(params);
@@ -90,4 +90,5 @@
     // Can't happen, validated earlier.
     IREE_UK_ASSUME_UNREACHABLE;
   }
+  return 0;
 }