Remove random_shuffle in C++17. Please use shuffle instead. If you have to, you cant get it back by defining _LIBCPP_ENABLE_CXX17_REMOVED_RANDOM_SHUFFLE before including any libc++ headers.

llvm-svn: 298597

4 files changed, 52 insertions, 2 deletions

diff --git a/libcxx/include/algorithm b/libcxx/include/algorithm
index 5eec80ca013..bba6d8d3d66 100644
--- a/libcxx/include/algorithm
+++ b/libcxx/include/algorithm
@@ -281,12 +281,12 @@ template <class ForwardIterator, class OutputIterator>
 
 template <class RandomAccessIterator>
     void
-    random_shuffle(RandomAccessIterator first, RandomAccessIterator last); // deprecated in C++14
+    random_shuffle(RandomAccessIterator first, RandomAccessIterator last); // deprecated in C++14, removed in C++17
 
 template <class RandomAccessIterator, class RandomNumberGenerator>
     void
     random_shuffle(RandomAccessIterator first, RandomAccessIterator last,
-                   RandomNumberGenerator& rand);  // deprecated in C++14
+                   RandomNumberGenerator& rand);  // deprecated in C++14, removed in C++17
 
 template<class PopulationIterator, class SampleIterator,
          class Distance, class UniformRandomBitGenerator>
@@ -3026,6 +3026,7 @@ uniform_int_distribution<_IntType>::operator()(_URNG& __g, const param_type& __p
     return static_cast<result_type>(__u + __p.a());
 }
 
+#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_RANDOM_SHUFFLE)
 class _LIBCPP_TYPE_VIS __rs_default;
 
 _LIBCPP_FUNC_VIS __rs_default __rs_get();
@@ -3095,6 +3096,7 @@ random_shuffle(_RandomAccessIterator __first, _RandomAccessIterator __last,
         }
     }
 }
+#endif
 
 template <class _PopulationIterator, class _SampleIterator, class _Distance,
           class _UniformRandomNumberGenerator>
diff --git a/libcxx/test/libcxx/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle.cxx1z.pass.cpp b/libcxx/test/libcxx/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle.cxx1z.pass.cpp
new file mode 100644
index 00000000000..8214e1e2068
--- /dev/null
+++ b/libcxx/test/libcxx/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle.cxx1z.pass.cpp
@@ -0,0 +1,46 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// <memory>
+
+// template <class RandomAccessIterator>
+//     void
+//     random_shuffle(RandomAccessIterator first, RandomAccessIterator last);
+// 
+// template <class RandomAccessIterator, class RandomNumberGenerator>
+//     void
+//     random_shuffle(RandomAccessIterator first, RandomAccessIterator last,
+//                    RandomNumberGenerator& rand);
+
+//
+//  In C++17, random_shuffle has been removed.
+//  However, for backwards compatibility, if _LIBCPP_ENABLE_CXX17_REMOVED_RANDOM_SHUFFLE
+//  is defined before including <algorithm>, then random_shuffle will be restored.
+
+#define _LIBCPP_ENABLE_CXX17_REMOVED_RANDOM_SHUFFLE
+
+#include <algorithm>
+#include <vector>
+
+struct gen
+{
+    std::ptrdiff_t operator()(std::ptrdiff_t n)
+    {
+        return n-1;
+    }
+};
+
+
+int main()
+{
+    std::vector<int> v;
+    std::random_shuffle(v.begin(), v.end());
+    gen r;
+    std::random_shuffle(v.begin(), v.end(), r);
+}
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle.pass.cpp
index e24598a9bc1..77d7153e4e2 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // <algorithm>
+// REQUIRES-ANY: c++98, c++03, c++11, c++14
 
 // template<RandomAccessIterator Iter>
 //   requires ShuffleIterator<Iter>
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle_rand.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle_rand.pass.cpp
index c923d847f11..2424c7732db 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle_rand.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.random.shuffle/random_shuffle_rand.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // <algorithm>
+// REQUIRES-ANY: c++98, c++03, c++11, c++14
 
 // template<RandomAccessIterator Iter, Callable<auto, Iter::difference_type> Rand>
 //   requires ShuffleIterator<Iter>