From 284844495422a295597af5b93cbd798e920f3c44 Mon Sep 17 00:00:00 2001
From: Howard Hinnant <hhinnant@apple.com>
Date: Wed, 15 Feb 2012 20:13:52 +0000
Subject: [PATCH] tuple was accidentally lacking a valid copy assignment
 operator.  It went undetected because I had failed to test assigning from a
 const lvalue.  This fixes http://llvm.org/bugs/show_bug.cgi?id=11921

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@150613 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/tuple                                             | 8 ++++++++
 .../tuple/tuple.tuple/tuple.assign/copy.pass.cpp          | 2 +-
 .../utilities/tuple/tuple.tuple/tuple.cnstr/copy.pass.cpp | 2 +-
 3 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/include/tuple b/include/tuple
index d5c6ad0b..2bdb05fb 100644
--- a/include/tuple
+++ b/include/tuple
@@ -500,6 +500,14 @@ struct __tuple_impl<__tuple_indices<_Indx...>, _Tp...>
             return *this;
         }
 
+        _LIBCPP_INLINE_VISIBILITY
+        __tuple_impl&
+        operator=(const __tuple_impl& __t)
+        {
+            __swallow(__tuple_leaf<_Indx, _Tp>::operator=(static_cast<const __tuple_leaf<_Indx, _Tp>&>(__t).get())...);
+            return *this;
+        }
+
     _LIBCPP_INLINE_VISIBILITY
     void swap(__tuple_impl& __t)
         _NOEXCEPT_(__all<__is_nothrow_swappable<_Tp>::value...>::value)
diff --git a/test/utilities/tuple/tuple.tuple/tuple.assign/copy.pass.cpp b/test/utilities/tuple/tuple.tuple/tuple.assign/copy.pass.cpp
index 45a06aa4..f19043ca 100644
--- a/test/utilities/tuple/tuple.tuple/tuple.assign/copy.pass.cpp
+++ b/test/utilities/tuple/tuple.tuple/tuple.assign/copy.pass.cpp
@@ -42,7 +42,7 @@ int main()
     }
     {
         typedef std::tuple<int, char, std::string> T;
-        T t0(2, 'a', "some text");
+        const T t0(2, 'a', "some text");
         T t;
         t = t0;
         assert(std::get<0>(t) == 2);
diff --git a/test/utilities/tuple/tuple.tuple/tuple.cnstr/copy.pass.cpp b/test/utilities/tuple/tuple.tuple/tuple.cnstr/copy.pass.cpp
index 0f0d1fb9..7de3ef61 100644
--- a/test/utilities/tuple/tuple.tuple/tuple.cnstr/copy.pass.cpp
+++ b/test/utilities/tuple/tuple.tuple/tuple.cnstr/copy.pass.cpp
@@ -39,7 +39,7 @@ int main()
     }
     {
         typedef std::tuple<int, char, std::string> T;
-        T t0(2, 'a', "some text");
+        const T t0(2, 'a', "some text");
         T t = t0;
         assert(std::get<0>(t) == 2);
         assert(std::get<1>(t) == 'a');