move.h (__is_nothrow_swappable): Add.

2011-06-22  Daniel Krugler  <daniel.kruegler@googlemail.com>
	    Paolo Carlini  <paolo.carlini@oracle.com>

	* include/bits/move.h (__is_nothrow_swappable): Add.
	(swap(_Tp(&)[_Nm], _Tp(&)[_Nm])): Use noexcept.
	* include/bits/algorithmfwd.h: Adjust.
	* testsuite/25_algorithms/swap/noexcept.cc: New.

Co-Authored-By: Paolo Carlini <paolo.carlini@oracle.com>
From-SVN: r175277

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index 77a5403ddbcb3f4787ebe3f87e5a6881b5988fe6..bd75196bc8857573e79770036d85f3141ffced2d 100644 (file)
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,11 @@
+2011-06-22  Daniel Krugler  <daniel.kruegler@googlemail.com>
+           Paolo Carlini  <paolo.carlini@oracle.com>
+
+       * include/bits/move.h (__is_nothrow_swappable): Add.
+       (swap(_Tp(&)[_Nm], _Tp(&)[_Nm])): Use noexcept.
+       * include/bits/algorithmfwd.h: Adjust.
+       * testsuite/25_algorithms/swap/noexcept.cc: New.
+
 2011-06-21  Jakub Jelinek  <jakub@redhat.com>
 
        * testsuite/Makefile.am (check_DEJAGNU_normal_targets): Add

diff --git a/libstdc++-v3/include/bits/algorithmfwd.h b/libstdc++-v3/include/bits/algorithmfwd.h
index bb7ca250333de21f189d41d0e7441c7d6d33fbc2..7bb9880ebebcf1d85a5613b84908817385de39b4 100644 (file)
--- a/libstdc++-v3/include/bits/algorithmfwd.h
+++ b/libstdc++-v3/include/bits/algorithmfwd.h
@@ -558,7 +558,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 
   template<typename _Tp, size_t _Nm>
     void
-    swap(_Tp (&)[_Nm], _Tp (&)[_Nm]);
+    swap(_Tp (&)[_Nm], _Tp (&)[_Nm])
+#ifdef __GXX_EXPERIMENTAL_CXX0X__
+    noexcept(__is_nothrow_swappable<_Tp>::value)
+#endif
+    ;
 
   template<typename _FIter1, typename _FIter2>
     _FIter2 

diff --git a/libstdc++-v3/include/bits/move.h b/libstdc++-v3/include/bits/move.h
index d791d69ae4d27e3e6623e078bce7e83318a23e4c..e82e36d892ed4314ad826a730050ccdf3f0fd19e 100644 (file)
--- a/libstdc++-v3/include/bits/move.h
+++ b/libstdc++-v3/include/bits/move.h
@@ -152,12 +152,22 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       __b = _GLIBCXX_MOVE(__tmp);
     }
 
+#ifdef __GXX_EXPERIMENTAL_CXX0X__
+  // To work around c++/49045.
+  template<typename _Tp>
+    struct __is_nothrow_swappable
+    { static const bool value = noexcept(swap(std::declval<_Tp&>(),
+                                             std::declval<_Tp&>())); };
+#endif
+
   // _GLIBCXX_RESOLVE_LIB_DEFECTS
   // DR 809. std::swap should be overloaded for array types.
   template<typename _Tp, size_t _Nm>
     inline void
     swap(_Tp (&__a)[_Nm], _Tp (&__b)[_Nm])
-    // noexcept waits for c++/49045
+#ifdef __GXX_EXPERIMENTAL_CXX0X__
+    noexcept(__is_nothrow_swappable<_Tp>::value)
+#endif
     {
       for (size_t __n = 0; __n < _Nm; ++__n)
        swap(__a[__n], __b[__n]);

diff --git a/libstdc++-v3/testsuite/25_algorithms/swap/noexcept.cc b/libstdc++-v3/testsuite/25_algorithms/swap/noexcept.cc
new file mode 100644 (file)
index 0000000..4d8c87a
--- /dev/null
+++ b/libstdc++-v3/testsuite/25_algorithms/swap/noexcept.cc
@@ -0,0 +1,26 @@
+// { dg-do compile }
+// { dg-options "-std=gnu++0x" }
+
+// Copyright (C) 2011 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/>.
+
+#include <utility>
+
+static_assert(noexcept(std::swap(std::declval<int&>(),
+                                std::declval<int&>())), "Error");
+static_assert(noexcept(std::swap(std::declval<int(&)[5]>(),
+                                std::declval<int(&)[5]>())), "Error");