From f491e51ebd3ac15bea38b6a826628dd9c4d13e19 Mon Sep 17 00:00:00 2001
From: Howard Hinnant <hhinnant@apple.com>
Date: Sat, 29 Jun 2013 18:38:17 +0000
Subject: [PATCH] Add operators to make launch a bitmask type.  Searched all of
 the standard, and libc++ to see if this error occurred elsewhere and didn't
 see any other place.  This fixes http://llvm.org/bugs/show_bug.cgi?id=16207

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@185265 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/future                                | 66 +++++++++++++++++++
 .../futures/futures.overview/launch.pass.cpp  | 16 +++++
 2 files changed, 82 insertions(+)

diff --git a/include/future b/include/future
index 3d7bb6c9..160114e5 100644
--- a/include/future
+++ b/include/future
@@ -403,6 +403,72 @@ _LIBCPP_DECLARE_STRONG_ENUM(launch)
 };
 _LIBCPP_DECLARE_STRONG_ENUM_EPILOG(launch)
 
+#ifndef _LIBCPP_HAS_NO_STRONG_ENUMS
+
+#ifdef _LIBCXX_UNDERLYING_TYPE
+typedef underlying_type<launch>::type __launch_underlying_type;
+#else
+typedef int __launch_underlying_type;
+#endif
+
+inline _LIBCPP_INLINE_VISIBILITY
+_LIBCPP_CONSTEXPR
+launch
+operator&(launch __x, launch __y)
+{
+    return static_cast<launch>(static_cast<__launch_underlying_type>(__x) &
+                               static_cast<__launch_underlying_type>(__y));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY
+_LIBCPP_CONSTEXPR
+launch
+operator|(launch __x, launch __y)
+{
+    return static_cast<launch>(static_cast<__launch_underlying_type>(__x) |
+                               static_cast<__launch_underlying_type>(__y));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY
+_LIBCPP_CONSTEXPR
+launch
+operator^(launch __x, launch __y)
+{
+    return static_cast<launch>(static_cast<__launch_underlying_type>(__x) ^
+                               static_cast<__launch_underlying_type>(__y));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY
+_LIBCPP_CONSTEXPR
+launch
+operator~(launch __x)
+{
+    return static_cast<launch>(~static_cast<__launch_underlying_type>(__x));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY
+launch&
+operator&=(launch& __x, launch __y)
+{
+    __x = __x & __y; return __x;
+}
+
+inline _LIBCPP_INLINE_VISIBILITY
+launch&
+operator|=(launch& __x, launch __y)
+{
+    __x = __x | __y; return __x;
+}
+
+inline _LIBCPP_INLINE_VISIBILITY
+launch&
+operator^=(launch& __x, launch __y)
+{
+    __x = __x ^ __y; return __x;
+}
+
+#endif  // !_LIBCPP_HAS_NO_STRONG_ENUMS
+
 //enum class future_status
 _LIBCPP_DECLARE_STRONG_ENUM(future_status)
 {
diff --git a/test/thread/futures/futures.overview/launch.pass.cpp b/test/thread/futures/futures.overview/launch.pass.cpp
index 75534f79..d634c8b5 100644
--- a/test/thread/futures/futures.overview/launch.pass.cpp
+++ b/test/thread/futures/futures.overview/launch.pass.cpp
@@ -17,11 +17,27 @@
 // };
 
 #include <future>
+#include <cassert>
 
 int main()
 {
+#ifdef _LIBCPP_HAS_NO_STRONG_ENUMS
     static_assert(static_cast<int>(std::launch::any) ==
                  (static_cast<int>(std::launch::async) | static_cast<int>(std::launch::deferred)), "");
+#else
+    static_assert(std::launch::any == (std::launch::async | std::launch::deferred), "");
+    static_assert(std::launch(0) == (std::launch::async & std::launch::deferred), "");
+    static_assert(std::launch::any == (std::launch::async ^ std::launch::deferred), "");
+    static_assert(std::launch(~1) == ~std::launch::async, "");
+    std::launch x = std::launch::async;
+    x &= std::launch::deferred;
+    assert(x == std::launch(0));
+    x = std::launch::async;
+    x |= std::launch::deferred;
+    assert(x == std::launch::any);
+    x ^= std::launch::deferred;
+    assert(x == std::launch::async);
+#endif
     static_assert(static_cast<int>(std::launch::async) == 1, "");
     static_assert(static_cast<int>(std::launch::deferred) == 2, "");
 }