-check return value

src/mint-lib/test_mint_api.c

@@ -1524,6 +1524,7 @@ interpreter_run (void *cls,
         fail (is);
         return;
       }
+      json_decref (wire);
       trigger_context_task ();
       return;
     }

src/mintdb/perf_taler_mintdb_interpreter.c

@@ -1735,7 +1735,7 @@ interpret (struct PERF_TALER_MINTDB_interpreter_state *state)
                                                             1,
                                                             1,
                                                             refresh_commit);
-                                                            
+          GNUNET_assert (GNUNET_OK == ret);                                                  
         }
         break;