diff --git a/src/var.c b/src/var.c
index 04539f9c..667a9ee5 100644
--- a/src/var.c
+++ b/src/var.c
@@ -1317,6 +1317,8 @@ PopVars(ParsePtr p)
 
             /* Destructively copy value */
             dest->v = src->v;
+
+            /* Make sure free_pushedvars doesn't destroy our value! */
             src->v.type = ERR_TYPE;
             src->v.v.val = 0;
         }