diff --git a/cpp/src/strings/regex/regexec.cu b/cpp/src/strings/regex/regexec.cu
index 99f6692f023..2ee1901c32d 100644
--- a/cpp/src/strings/regex/regexec.cu
+++ b/cpp/src/strings/regex/regexec.cu
@@ -109,7 +109,7 @@ std::unique_ptr<reprog_device, std::function<void(reprog_device*)>> reprog_devic
   auto d_end = d_ptr + (classes_count * sizeof(reclass_device));
   // place each class and append the variable length data
   for (int32_t idx = 0; idx < classes_count; ++idx) {
-    auto h_class = h_prog.class_at(idx);
+    auto const& h_class = h_prog.class_at(idx);
     reclass_device d_class{h_class.builtins,
                            static_cast<int32_t>(h_class.literals.size()),
                            reinterpret_cast<reclass_range*>(d_end)};