[libcxx-commits] [libcxx] r363075 - [libcxx] Make std::tuple<> trivially constructible

[Louis Dionne via libcxx-commits]

Author: ldionne
Date: Tue Jun 11 08:02:10 2019
New Revision: 363075

URL: http://llvm.org/viewvc/llvm-project?rev=363075&view=rev
Log:
[libcxx] Make std::tuple<> trivially constructible

Summary:
This is not mandated by the Standard, but it's nonetheless a nice
property to have, especially since it's so easy to implement. It
also shrinks our bug list!

PR41714

Reviewers: mclow.lists, EricWF

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D62618

Added:
    libcxx/trunk/test/libcxx/utilities/tuple/tuple.tuple/tuple.cnstr/empty_tuple_trivial.pass.cpp
Modified:
    libcxx/trunk/include/tuple

Modified: libcxx/trunk/include/tuple
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/include/tuple?rev=363075&r1=363074&r2=363075&view=diff
==============================================================================
--- libcxx/trunk/include/tuple (original)
+++ libcxx/trunk/include/tuple Tue Jun 11 08:02:10 2019
@@ -907,7 +907,7 @@ class _LIBCPP_TEMPLATE_VIS tuple<>
 {
 public:
     _LIBCPP_INLINE_VISIBILITY
-    _LIBCPP_CONSTEXPR tuple() _NOEXCEPT {}
+    _LIBCPP_CONSTEXPR tuple() _NOEXCEPT = default;
     template <class _Alloc>
     _LIBCPP_INLINE_VISIBILITY
         tuple(allocator_arg_t, const _Alloc&) _NOEXCEPT {}

Added: libcxx/trunk/test/libcxx/utilities/tuple/tuple.tuple/tuple.cnstr/empty_tuple_trivial.pass.cpp
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/test/libcxx/utilities/tuple/tuple.tuple/tuple.cnstr/empty_tuple_trivial.pass.cpp?rev=363075&view=auto
==============================================================================
--- libcxx/trunk/test/libcxx/utilities/tuple/tuple.tuple/tuple.cnstr/empty_tuple_trivial.pass.cpp (added)
+++ libcxx/trunk/test/libcxx/utilities/tuple/tuple.tuple/tuple.cnstr/empty_tuple_trivial.pass.cpp Tue Jun 11 08:02:10 2019
@@ -0,0 +1,22 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// This test ensures that std::tuple<> is trivially constructible. That is not
+// required by the Standard, but libc++ provides that guarantee.
+
+// UNSUPPORTED: c++98, c++03
+
+#include <tuple>
+#include <type_traits>
+
+
+static_assert(std::is_trivially_constructible<std::tuple<>>::value, "");
+
+int main(int, char**) {
+  return 0;
+}