message: llvm: fix parsing of return type
diff: @@ -555,7 +555,12 @@ public:
  assert(i.getType()->isVoidTy());
  return make_unique<Return>(Type::voidTy, Value::voidVal);
  }
  - PARSE_UNOP();
  +
  + auto ty = llvm_type2alive(i.getOperand(0)->getType());
  + auto val = get_operand(i.getOperand(0));
  + if (!ty || !val)
  + return error(i);
  +
  return make_unique<Return>(*ty, *val);
  }
  