diff --git a/src/include/varrec.cpp b/src/include/varrec.cpp
index 2629a33ca..158bd738c 100755
--- a/src/include/varrec.cpp
+++ b/src/include/varrec.cpp
@@ -185,7 +185,8 @@ void TVariable_rectype::update_memo()
 				t << '=' << val;
 			}
 		}
-		put(_memo_fld, t);
+		if (get(_memo_fld) != t)
+			put(_memo_fld, t);
 	}
 }