diff --git a/src/hb-dsalgs.hh b/src/hb-dsalgs.hh
index a7d9616b1..b5abb6db1 100644
--- a/src/hb-dsalgs.hh
+++ b/src/hb-dsalgs.hh
@@ -250,7 +250,7 @@ hb_ctz (T v)
  */
 
 template <typename T>
-static inline T* hb_addressof (T& arg)
+static inline T* hb_addressof (const T& arg)
 {
   /* https://en.cppreference.com/w/cpp/memory/addressof */
   return reinterpret_cast<T*>(