lexical #17/19, rewrite

src/frontend/parser/lexical.c

@@ -197,11 +197,12 @@ gotchar:
                 buf[i] = '\0';
                 newword;
             }
-            append(NULL);
-                if (cw->wl_prev) {
+                if (cw) {
+                    append(NULL);
                     cw->wl_prev->wl_next = NULL;
                     tfree(cw);
                 } else {
+                    append(NULL);
                     cw->wl_word = NULL;
                 }
             goto done;