PR libstdc++/40925 (again)

2009-10-29  Paolo Carlini  <paolo.carlini@oracle.com>
  	    Douglas Gregor  <doug.gregor@gmail.com>

	PR libstdc++/40925 (again)
	* include/bits/stl_pair.h (pair<_T1, _T2>::pair(_U1&&, const _T2&),
	pair<_T1, _T2>::pair(const _T1&, _U2&&)): Add, to deal correctly
	with move-only types in the presence of "null pointers".
	* testsuite/20_util/pair/40925.cc: Extend.

Co-Authored-By: Douglas Gregor <doug.gregor@gmail.com>

From-SVN: r153733

libstdc++-v3/ChangeLog

 2009-10-29  Paolo Carlini  <paolo.carlini@oracle.com>
+  	    Douglas Gregor  <doug.gregor@gmail.com>
+
+	PR libstdc++/40925 (again)
+	* include/bits/stl_pair.h (pair<_T1, _T2>::pair(_U1&&, const _T2&),
+	pair<_T1, _T2>::pair(const _T1&, _U2&&)): Add, to deal correctly
+	with move-only types in the presence of "null pointers".
+	* testsuite/20_util/pair/40925.cc: Extend.
+
+2009-10-29  Paolo Carlini  <paolo.carlini@oracle.com>
 
 	* include/std/type_traits (__is_int_or_cref): Remove.
 	(__is_convertible_helper): Fix per C++0x and simplify (the hack to

libstdc++-v3/include/bits/stl_pair.h

@@ -88,10 +88,23 @@ _GLIBCXX_BEGIN_NAMESPACE(std)
       : first(__a), second(__b) { }
 
 #ifdef __GXX_EXPERIMENTAL_CXX0X__
-      template<class _U1, class _U2>
-        pair(_U1&& __x, _U2&& __y, typename
-	    std::enable_if<std::is_convertible<_U1, _T1>::value
-	                   && std::is_convertible<_U2, _T2>::value>::type* = 0)
+      // DR 811.
+      template<class _U1, class = typename
+	       std::enable_if<std::is_convertible<_U1, _T1>::value>::type>
+        pair(_U1&& __x, const _T2& __y)
+	: first(std::forward<_U1>(__x)),
+	  second(__y) { }
+
+      template<class _U2, class = typename
+	       std::enable_if<std::is_convertible<_U2, _T2>::value>::type>
+        pair(const _T1& __x, _U2&& __y)
+	: first(__x),
+	  second(std::forward<_U2>(__y)) { }
+
+      template<class _U1, class _U2, class = typename
+	       std::enable_if<std::is_convertible<_U1, _T1>::value
+			      && std::is_convertible<_U2, _T2>::value>::type>
+        pair(_U1&& __x, _U2&& __y)
 	: first(std::forward<_U1>(__x)),
 	  second(std::forward<_U2>(__y)) { }
 

libstdc++-v3/testsuite/20_util/pair/40925.cc

@@ -28,6 +28,15 @@ private:
   X(const X&) = delete;
 };
 
+struct move_only
+{
+  move_only() { }
+  move_only(move_only&&) { }
+
+private:
+  move_only(const move_only&) = delete;
+};
+
 // libstdc++/40925
 void test01()
 {
@@ -43,4 +52,16 @@ void test01()
   std::pair<int X::*, int X::*> p6(mp, 0);
   std::pair<int X::*, int X::*> p7(0, mp);
   std::pair<int X::*, int X::*> p8(mp, mp);
+
+  std::pair<int*, move_only> p9(0, move_only());
+  std::pair<int X::*, move_only> p10(0, move_only());
+  std::pair<move_only, int*> p11(move_only(), 0);
+  std::pair<move_only, int X::*> p12(move_only(), 0);
+
+  std::pair<int*, move_only> p13(ip, move_only());
+  std::pair<int X::*, move_only> p14(mp, move_only());
+  std::pair<move_only, int*> p15(move_only(), ip);
+  std::pair<move_only, int X::*> p16(move_only(), mp);
+
+  std::pair<move_only, move_only> p17(move_only(), move_only());
 }