From ebe16361b0f1151970e715882cca0874d5236b11 Mon Sep 17 00:00:00 2001
From: Wenzel Jakob <wenzel.jakob@epfl.ch>
Date: Tue, 6 Feb 2018 00:13:38 +0100
Subject: [PATCH] Fix pybind11 interoperability with Clang trunk

---
 include/pybind11/cast.h | 3 +++
 include/pybind11/stl.h  | 3 ++-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/include/pybind11/cast.h b/include/pybind11/cast.h
index 1010ae3e8..a722a9e81 100644
--- a/include/pybind11/cast.h
+++ b/include/pybind11/cast.h
@@ -1686,6 +1686,9 @@ template <> inline void cast_safe<void>(object &&) {}
 
 NAMESPACE_END(detail)
 
+template <return_value_policy policy = return_value_policy::automatic_reference>
+tuple make_tuple() { return tuple(0); }
+
 template <return_value_policy policy = return_value_policy::automatic_reference,
           typename... Args> tuple make_tuple(Args&&... args_) {
     constexpr size_t size = sizeof...(Args);
diff --git a/include/pybind11/stl.h b/include/pybind11/stl.h
index db900e674..90eb7ea2e 100644
--- a/include/pybind11/stl.h
+++ b/include/pybind11/stl.h
@@ -30,7 +30,8 @@
 #    define PYBIND11_HAS_OPTIONAL 1
 #  endif
 // std::experimental::optional (but not allowed in c++11 mode)
-#  if defined(PYBIND11_CPP14) && __has_include(<experimental/optional>)
+#  if defined(PYBIND11_CPP14) && (__has_include(<experimental/optional>) && \
+                                 !__has_include(<optional>))
 #    include <experimental/optional>
 #    define PYBIND11_HAS_EXP_OPTIONAL 1
 #  endif