From 6a683bfb5fbf87fc37e155b3146094697a87b86f Mon Sep 17 00:00:00 2001
From: Howard Hinnant <hhinnant@apple.com>
Date: Tue, 2 Jul 2013 18:01:41 +0000
Subject: [PATCH] Constrain launch ~ operator to defined bits.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@185452 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/future                                       | 2 +-
 test/thread/futures/futures.overview/launch.pass.cpp | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/future b/include/future
index 160114e5..dae1a4b8 100644
--- a/include/future
+++ b/include/future
@@ -443,7 +443,7 @@ _LIBCPP_CONSTEXPR
 launch
 operator~(launch __x)
 {
-    return static_cast<launch>(~static_cast<__launch_underlying_type>(__x));
+    return static_cast<launch>(~static_cast<__launch_underlying_type>(__x) & 3);
 }
 
 inline _LIBCPP_INLINE_VISIBILITY
diff --git a/test/thread/futures/futures.overview/launch.pass.cpp b/test/thread/futures/futures.overview/launch.pass.cpp
index d634c8b5..5f4663ca 100644
--- a/test/thread/futures/futures.overview/launch.pass.cpp
+++ b/test/thread/futures/futures.overview/launch.pass.cpp
@@ -28,7 +28,7 @@ int main()
     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, "");
+    static_assert(std::launch::deferred == ~std::launch::async, "");
     std::launch x = std::launch::async;
     x &= std::launch::deferred;
     assert(x == std::launch(0));