diff --git a/src/cossim.cpp b/src/cossim.cpp
index 6044d61..749411b 100644
--- a/src/cossim.cpp
+++ b/src/cossim.cpp
@@ -11,7 +11,7 @@ BEGIN_RCPP
   int sizea=a.size();
   int sizeb=b.size();
   if(sizea != sizeb) {
-    Rf_error("incompatible dimensions");
+    Rcpp::stop("incompatible dimensions");
   }
   NumericVector res(1);