put_complete_string should push the empty list to the heap for empty strings (#1209)

diff --git a/src/machine/heap.rs b/src/machine/heap.rs
index 6a5e14ef7115d4218176f0e535dc9feda8f25413..a7317cc348e4e09ecc998591704ac9cc4ff7acd1 100644 (file)
--- a/src/machine/heap.rs
+++ b/src/machine/heap.rs
@@ -147,7 +147,9 @@ pub(crate) fn put_complete_string(
             }
         }
         None => {
-            empty_list_as_cell!()
+            let h = heap.len();
+            heap.push(empty_list_as_cell!());
+            heap_loc_as_cell!(h)
         }
     }
 }