PR libstdc++/85642 fix is_nothrow_default_constructible<optional<T>>

Add missing noexcept keyword to default constructor of each
_Optional_payload specialization.

	PR libstdc++/85642 fix is_nothrow_default_constructible<optional<T>>
	* include/std/optional (_Optional_payload): Add noexcept to default
	constructor. Re-indent.
	(_Optional_payload<_Tp, true, true, true>): Likewise. Add noexcept to
	constructor for copying disengaged payloads.
	(_Optional_payload<_Tp, true, false, true>): Likewise.
	(_Optional_payload<_Tp, true, true, false>): Likewise.
	(_Optional_payload<_Tp, true, false, false>): Likewise.
	* testsuite/20_util/optional/cons/85642.cc: New.
	* testsuite/20_util/optional/cons/value_neg.cc: Adjust dg-error lines.

From-SVN: r259928

libstdc++-v3/ChangeLog

+2018-05-04  Jonathan Wakely  <jwakely@redhat.com>
+
+	PR libstdc++/85642 fix is_nothrow_default_constructible<optional<T>>
+	* include/std/optional (_Optional_payload): Add noexcept to default
+	constructor. Re-indent.
+	(_Optional_payload<_Tp, true, true, true>): Likewise. Add noexcept to
+	constructor for copying disengaged payloads.
+	(_Optional_payload<_Tp, true, false, true>): Likewise.
+	(_Optional_payload<_Tp, true, true, false>): Likewise.
+	(_Optional_payload<_Tp, true, false, false>): Likewise.
+	* testsuite/20_util/optional/cons/85642.cc: New.
+	* testsuite/20_util/optional/cons/value_neg.cc: Adjust dg-error lines.
+
 2018-05-03  Jonathan Wakely  <jwakely@redhat.com>
 
 	PR libstdc++/82644

libstdc++-v3/testsuite/20_util/optional/cons/85642.cc

+// Copyright (C) 2018 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-options "-std=gnu++17" }
+// { dg-do compile { target c++17 } }
+
+#include <optional>
+
+struct NonTrivialDtor {
+  ~NonTrivialDtor() { }
+};
+
+struct NonTrivialCopyAssign {
+  NonTrivialCopyAssign& operator=(const NonTrivialCopyAssign&) { return *this; }
+  NonTrivialCopyAssign& operator=(NonTrivialCopyAssign&&) = default;
+};
+
+struct NonTrivialMoveAssign {
+  NonTrivialMoveAssign& operator=(const NonTrivialMoveAssign&) = default;
+  NonTrivialMoveAssign& operator=(NonTrivialMoveAssign&&) { return *this; }
+};
+
+struct NonTrivialAssign {
+  NonTrivialAssign& operator=(const NonTrivialAssign&) { return *this; }
+  NonTrivialAssign& operator=(NonTrivialAssign&&) { return *this; }
+};
+
+struct NonTrivialAll {
+  ~NonTrivialAll() { }
+  NonTrivialAll& operator=(const NonTrivialAll&) { return *this; }
+  NonTrivialAll& operator=(NonTrivialAll&&) { return *this; }
+};
+
+struct ConstExpr { int i = 0; };
+
+struct Trivial { int i; };
+
+template<typename T>
+  constexpr bool check
+    = std::is_nothrow_default_constructible_v<std::optional<T>>;
+
+// PR libstdc++/85642
+static_assert(check<NonTrivialDtor>);
+static_assert(check<NonTrivialCopyAssign>);
+static_assert(check<NonTrivialMoveAssign>);
+static_assert(check<NonTrivialAssign>);
+static_assert(check<NonTrivialAll>);
+static_assert(check<ConstExpr>);
+static_assert(check<Trivial>);

libstdc++-v3/testsuite/20_util/optional/cons/value_neg.cc

@@ -37,8 +37,8 @@ int main()
     std::optional<std::unique_ptr<int>> oup2 = new int;  // { dg-error "conversion" }
     struct U { explicit U(std::in_place_t); };
     std::optional<U> ou(std::in_place); // { dg-error "no matching" }
-    // { dg-error "no type" "" { target { *-*-* } } 1015 }
-    // { dg-error "no type" "" { target { *-*-* } } 1025 }
-    // { dg-error "no type" "" { target { *-*-* } } 1082 }
+    // { dg-error "no type" "" { target { *-*-* } } 1020 }
+    // { dg-error "no type" "" { target { *-*-* } } 1030 }
+    // { dg-error "no type" "" { target { *-*-* } } 1087 }
   }
 }