try to reload only when mc_deck is available

comment modified

src/frontend/inp.c

@@ -468,7 +468,7 @@ inp_spsource(FILE *fp, bool comfile, char *filename, bool intfile)
     /* called with *fp == NULL and not intfile: we want to reload circuit from mc_deck */
     else {
         /* re-load deck due to command 'reset' via function inp_source_recent() */
-        if (mc_reload) {
+        if (mc_reload && mc_deck) {
             deck = inp_deckcopy(mc_deck);
             expr_w_temper = TRUE;
             mc_reload = FALSE;
@@ -479,14 +479,14 @@ inp_spsource(FILE *fp, bool comfile, char *filename, bool intfile)
             deck = inp_deckcopy(ft_curckt->ci_mcdeck);
             expr_w_temper = TRUE;
         }
-        /* re-load input deck from the recent circuit structure */
+        /* re-load input deck from the recent circuit structure with mc_source */
         else if (!ft_curckt && mc_deck) {
             deck = inp_deckcopy(mc_deck);
             expr_w_temper = TRUE;
         }
         /* no circuit available, should not happen */
         else {
-            fprintf(stderr, "Error: No circuit loaded, cannot copy internally using mc_source\n");
+            fprintf(stderr, "Error: No circuit loaded, cannot copy internally using mc_source or reset\n");
             controlled_exit(1);
         }
         /* print out the re-loaded deck into debug-out-mc.txt */