1 files changed, 1 insertions, 1 deletions
diff --git a/gr-blocks/lib/annotator_raw_impl.h b/gr-blocks/lib/annotator_raw_impl.h
index 9bce4031dc..7c8093ea1b 100644
--- a/gr-blocks/lib/annotator_raw_impl.h
+++ b/gr-blocks/lib/annotator_raw_impl.h
@@ -20,7 +20,7 @@ namespace blocks {
 class annotator_raw_impl : public annotator_raw
 {
 private:
-    size_t d_itemsize;
+    const size_t d_itemsize;
     std::vector<tag_t> d_queued_tags;
     gr::thread::mutex d_mutex;