#3711 fix

src/vm.c

@@ -1894,9 +1894,13 @@ RETRY_TRY_BLOCK:
           }
           /* call ensure only when we skip this callinfo */
           if (ci[0].ridx == ci[-1].ridx) {
+	    mrb_value *org_stbase = mrb->c->stbase;
             while (mrb->c->eidx > ci->epos) {
               ecall(mrb, --mrb->c->eidx);
               ci = mrb->c->ci;
+	      if (org_stbase != mrb->c->stbase) {
+		stk = mrb->c->stack;
+	      }
             }
           }
         }