Future: some fixes re: handling of universal references

[folly.git] / folly / futures / helpers.h

diff --git a/folly/futures/helpers.h b/folly/futures/helpers.h
index 7f074a06664a5a363db0cb64508d3e7b3ae2d4c3..26187b8fa0662316bf66ca97471edb7c3364c854 100644 (file)
--- a/folly/futures/helpers.h
+++ b/folly/futures/helpers.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2016 Facebook, Inc.
+ * Copyright 2017 Facebook, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -148,7 +148,7 @@ inline Future<Unit> via(
 /// easier to read and slightly more efficient.
 template <class Func>
 auto via(Executor*, Func&& func)
-  -> Future<typename isFuture<decltype(func())>::Inner>;
+    -> Future<typename isFuture<decltype(std::declval<Func>()())>::Inner>;
 
 /** When all the input Futures complete, the returned Future will complete.
   Errors do not cause early termination; this Future will always succeed
@@ -363,6 +363,9 @@ namespace futures {
  *  indicating that the failure was transitory.
  *
  *  Cancellation is not supported.
+ *
+ *  If both FF and Policy inline executes, then it is possible to hit a stack
+ *  overflow due to the recursive nature of the retry implementation
  */
 template <class Policy, class FF>
 typename std::result_of<FF(size_t)>::type