folly: fix make_optional compliation issue with gnu++17

[folly.git] / folly / Optional.h

diff --git a/folly/Optional.h b/folly/Optional.h
index 60ae2c735b1152ca2c883263c483b4ca229af386..ecce46e225ff0fc8befe28661ac7a43f3d017938 100644 (file)
--- a/folly/Optional.h
+++ b/folly/Optional.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 Facebook, Inc.
+ * Copyright 2012-present Facebook, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -13,7 +13,6 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-
 #pragma once
 
 /*
@@ -87,7 +86,7 @@ typedef int detail::NoneHelper::*None;
 
 const None none = nullptr;
 
-class OptionalEmptyException : public std::runtime_error {
+class FOLLY_EXPORT OptionalEmptyException : public std::runtime_error {
  public:
   OptionalEmptyException()
       : std::runtime_error("Empty Optional cannot be unwrapped") {}