--- a/libinterp/octave-value/ov-cell.h	Sat Sep 04 07:50:08 2021 -0400
+++ b/libinterp/octave-value/ov-cell.h	Tue Sep 07 14:39:08 2021 -0700
@@ -52,17 +52,17 @@
 public:
 
   octave_cell (void)
-    : octave_base_matrix<Cell> (), cellstr_cache () { }
+    : octave_base_matrix<Cell> (), m_cellstr_cache () { }
 
   octave_cell (const Cell& c)
-    : octave_base_matrix<Cell> (c), cellstr_cache () { }
+    : octave_base_matrix<Cell> (c), m_cellstr_cache () { }
 
   octave_cell (const Array<std::string>& str)
     : octave_base_matrix<Cell> (Cell (str)),
-      cellstr_cache (new Array<std::string> (str)) { }
+      m_cellstr_cache (new Array<std::string> (str)) { }
 
   octave_cell (const octave_cell& c)
-    : octave_base_matrix<Cell> (c), cellstr_cache () { }
+    : octave_base_matrix<Cell> (c), m_cellstr_cache () { }
 
   ~octave_cell (void) = default;
 
@@ -183,9 +183,11 @@
 private:
 
   void clear_cellstr_cache (void) const
-  { cellstr_cache.reset (); }
+  { m_cellstr_cache.reset (); }
 
-  mutable std::unique_ptr<Array<std::string>> cellstr_cache;
+  //--------
+
+  mutable std::unique_ptr<Array<std::string>> m_cellstr_cache;
 
   DECLARE_OV_TYPEID_FUNCTIONS_AND_DATA
 };