From a16bc2f317ddfeb45a6b293aec4d89afe0e79a72 Mon Sep 17 00:00:00 2001
From: Jonathan Wakely <jwakely@redhat.com>
Date: Tue, 1 Oct 2019 22:02:27 +0100
Subject: [PATCH] Make some new algorithms work in parallel mode

	* include/experimental/algorithm (experimental::sample): Qualify call
	to __sample correctly.
	* include/parallel/algo.h (sample, for_each_n): Add using-declarations
	for algorithms that don't have parallel implementations.

From-SVN: r276432
---
 libstdc++-v3/ChangeLog                      | 5 +++++
 libstdc++-v3/include/experimental/algorithm | 6 +++---
 libstdc++-v3/include/parallel/algo.h        | 5 +++++
 3 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index 45ad8517bf4..9cf1c9a52c4 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,5 +1,10 @@
 2019-10-01  Jonathan Wakely  <jwakely@redhat.com>
 
+	* include/experimental/algorithm (experimental::sample): Qualify call
+	to __sample correctly.
+	* include/parallel/algo.h (sample, for_each_n): Add using-declarations
+	for algorithms that don't have parallel implementations.
+
 	* include/parallel/algobase.h (equal, lexicographical_compare): Add
 	_GLIBCXX20_CONSTEXPR and dispatch to sequential algorithm when being
 	constant evaluated.
diff --git a/libstdc++-v3/include/experimental/algorithm b/libstdc++-v3/include/experimental/algorithm
index 8ba212c5132..f036a713ef3 100644
--- a/libstdc++-v3/include/experimental/algorithm
+++ b/libstdc++-v3/include/experimental/algorithm
@@ -77,9 +77,9 @@ inline namespace fundamentals_v2
 		    "sample size must be an integer type");
 
       typename iterator_traits<_PopulationIterator>::difference_type __d = __n;
-      return std::__sample(__first, __last, __pop_cat{}, __out, __samp_cat{},
-			   __d,
-			   std::forward<_UniformRandomNumberGenerator>(__g));
+      return _GLIBCXX_STD_A::
+	__sample(__first, __last, __pop_cat{}, __out, __samp_cat{}, __d,
+		 std::forward<_UniformRandomNumberGenerator>(__g));
     }
 
   template<typename _PopulationIterator, typename _SampleIterator,
diff --git a/libstdc++-v3/include/parallel/algo.h b/libstdc++-v3/include/parallel/algo.h
index afa325bb4af..ab0540c1129 100644
--- a/libstdc++-v3/include/parallel/algo.h
+++ b/libstdc++-v3/include/parallel/algo.h
@@ -2189,6 +2189,11 @@ namespace __parallel
       return __min_element_switch(__begin, __end, __comp,
 				  std::__iterator_category(__begin));
     }
+
+#if __cplusplus >= 201703L
+  using _GLIBCXX_STD_A::for_each_n;
+  using _GLIBCXX_STD_A::sample;
+#endif
 } // end namespace
 } // end namespace
 
-- 
2.30.2