diff --git a/core/foundation/inc/ROOT/span.hxx b/core/foundation/inc/ROOT/span.hxx
index 640f59d47aa282..f458c778f9b64a 100644
--- a/core/foundation/inc/ROOT/span.hxx
+++ b/core/foundation/inc/ROOT/span.hxx
@@ -225,7 +225,7 @@ public:
      : length_(l.size()), data_(std::begin(l))
   {}
 
-  span& operator=(span const&) noexcept = delete;
+  span& operator=(span const&) noexcept = default;
   span& operator=(span &&) noexcept = delete;
 
   /*
@@ -432,8 +432,8 @@ private:
   }
 
 private:
-  index_type const length_;
-  pointer const data_;
+  index_type length_;
+  pointer data_;
 };
 // }}}
 } // inline namespace __ROOT
diff --git a/roofit/roofitcore/inc/RooSpan.h b/roofit/roofitcore/inc/RooSpan.h
index f1255c7995ffd5..4523f96ef98c2d 100644
--- a/roofit/roofitcore/inc/RooSpan.h
+++ b/roofit/roofitcore/inc/RooSpan.h
@@ -101,6 +101,9 @@ class RooSpan {
   { }
 
 
+  RooSpan<T>& operator=(const RooSpan<T>& other) = default;
+
+
   constexpr typename std::span<T>::iterator begin() const {
     return _span.begin();
   }