forward_list.h (forward_list<>::erase_after): Change signature per N2988, return void; simplify.

2009-11-13  Paolo Carlini  <paolo.carlini@oracle.com>

	* include/bits/forward_list.h (forward_list<>::erase_after):
	Change signature per N2988, return void; simplify.
	(_Fwd_list_base<>::_M_erase_after): Likewise return void.
	(forward_list<>::~forward_list): Do not call _M_erase_after
	unnecessarily, the base class destructor already does it.
	(forward_list<>::splice_after(const_iterator position,
	forward_list&&, const_iterator i): Check position != i and
	position != ++i.
	* include/bits/forward_list.tcc (_Fwd_list_base<>::
	_M_erase_after(typename _Node_base::_Pointer): Simplify.
	(_Fwd_list_base<>::_M_erase_after(typename _Node_base::_Pointer,
	typename _Node_base::_Pointer): Fix (remove the correct range
	of element) and simplify (update __pos->_M_next at the end).
	* testsuite/23_containers/forward_list/modifiers/3.cc: Adjust
	and extend.
	* testsuite/23_containers/forward_list/ext_pointer/
	modifiers/3.cc: Likewise.
	* testsuite/23_containers/forward_list/requirements/dr438/
	assign_neg.cc: Tweak dg-error line numbers.
	* testsuite/23_containers/forward_list/requirements/dr438/
	insert_neg.cc: Likewise.
	* testsuite/23_containers/forward_list/requirements/dr438/
	constructor_1_neg.cc: Likewise.
	* testsuite/23_containers/forward_list/requirements/dr438/
	constructor_2_neg.cc: Likewise.

From-SVN: r154174

9 files changed, 86 insertions, 57 deletions

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index a5f6383..53a7387 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,5 +1,33 @@
 2009-11-13  Paolo Carlini  <paolo.carlini@oracle.com>
 
+	* include/bits/forward_list.h (forward_list<>::erase_after):
+	Change signature per N2988, return void; simplify.
+	(_Fwd_list_base<>::_M_erase_after): Likewise return void.
+	(forward_list<>::~forward_list): Do not call _M_erase_after
+	unnecessarily, the base class destructor already does it.
+	(forward_list<>::splice_after(const_iterator position,
+	forward_list&&, const_iterator i): Check position != i and
+	position != ++i.
+	* include/bits/forward_list.tcc (_Fwd_list_base<>::
+	_M_erase_after(typename _Node_base::_Pointer): Simplify.
+	(_Fwd_list_base<>::_M_erase_after(typename _Node_base::_Pointer,
+	typename _Node_base::_Pointer): Fix (remove the correct range
+	of element) and simplify (update __pos->_M_next at the end).
+	* testsuite/23_containers/forward_list/modifiers/3.cc: Adjust
+	and extend.
+	* testsuite/23_containers/forward_list/ext_pointer/
+	modifiers/3.cc: Likewise.
+	* testsuite/23_containers/forward_list/requirements/dr438/
+	assign_neg.cc: Tweak dg-error line numbers.
+	* testsuite/23_containers/forward_list/requirements/dr438/
+	insert_neg.cc: Likewise.
+	* testsuite/23_containers/forward_list/requirements/dr438/
+	constructor_1_neg.cc: Likewise.
+	* testsuite/23_containers/forward_list/requirements/dr438/
+	constructor_2_neg.cc: Likewise.
+
+2009-11-13  Paolo Carlini  <paolo.carlini@oracle.com>
+
 	* include/std/algorithm: Include <utility>, per UK-300.
 	* include/bits/stl_algobase.h: Don't do it here.
 
diff --git a/libstdc++-v3/include/bits/forward_list.h b/libstdc++-v3/include/bits/forward_list.h
index 0ec5a11..409c93e 100644
--- a/libstdc++-v3/include/bits/forward_list.h
+++ b/libstdc++-v3/include/bits/forward_list.h
@@ -350,10 +350,10 @@ _GLIBCXX_BEGIN_NAMESPACE(std)
       _M_put_node(typename _Node::_Pointer __p)
       { _M_get_Node_allocator().deallocate(__p, 1); }
 
-      typename _Node_base::_Pointer
+      void
       _M_erase_after(typename _Node_base::_Pointer __pos);
 
-      typename _Node_base::_Pointer
+      void
       _M_erase_after(typename _Node_base::_Pointer __pos, 
                      typename _Node_base::_Pointer __last);
     };
@@ -529,7 +529,7 @@ _GLIBCXX_BEGIN_NAMESPACE(std)
        *  @brief  The forward_list dtor.
        */
       ~forward_list()
-      { _M_erase_after(&this->_M_impl._M_head, 0); }
+      { }
 
       /**
        *  @brief  The %forward_list assignment operator.
@@ -871,7 +871,7 @@ _GLIBCXX_BEGIN_NAMESPACE(std)
       insert_after(const_iterator __pos, size_type __n, const _Tp& __val)
       {
         forward_list __tmp(__n, __val, this->get_allocator());
-        this->splice_after(__pos, std::move(__tmp));
+        splice_after(__pos, std::move(__tmp));
       }
 
       /**
@@ -893,7 +893,7 @@ _GLIBCXX_BEGIN_NAMESPACE(std)
                      _InputIterator __first, _InputIterator __last)
         {
           forward_list __tmp(__first, __last, this->get_allocator());
-          this->splice_after(__pos, std::move(__tmp));
+          splice_after(__pos, std::move(__tmp));
         }
 
       /**
@@ -913,14 +913,13 @@ _GLIBCXX_BEGIN_NAMESPACE(std)
       insert_after(const_iterator __pos, std::initializer_list<_Tp> __il)
       {
         forward_list __tmp(__il, this->get_allocator());
-        this->splice_after(__pos, std::move(__tmp));
+        splice_after(__pos, std::move(__tmp));
       }
 
       /**
        *  @brief  Removes the element pointed to by the iterator following
        *          @c pos.
-       *  @param  pos  Iterator pointing to element to be erased.
-       *  @return  An iterator pointing to the next element (or end()).
+       *  @param  pos  Iterator pointing before element to be erased.
        *
        *  This function will erase the element at the given position and
        *  thus shorten the %forward_list by one.
@@ -932,14 +931,11 @@ _GLIBCXX_BEGIN_NAMESPACE(std)
        *  is itself a pointer, the pointed-to memory is not touched in
        *  any way.  Managing the pointer is the user's responsibility.
        */
-      iterator
+      void
       erase_after(const_iterator __pos)
       {
         _Node_base* __tmp = __const_pointer_cast<_Node_base*>(__pos._M_node);
-        if (__tmp)
-          return iterator(this->_M_erase_after(__tmp));
-        else
-          return end();
+	this->_M_erase_after(__tmp);
       }
 
       /**
@@ -948,8 +944,6 @@ _GLIBCXX_BEGIN_NAMESPACE(std)
        *               erased.
        *  @param  last  Iterator pointing to one past the last element to be
        *                erased.
-       *  @return  An iterator pointing to the element pointed to by @a last
-       *           prior to erasing (or end()).
        *
        *  This function will erase the elements in the range @a
        *  (pos,last) and shorten the %forward_list accordingly.
@@ -961,11 +955,12 @@ _GLIBCXX_BEGIN_NAMESPACE(std)
        *  pointed-to memory is not touched in any way.  Managing the pointer
        *  is the user's responsibility.
        */
-      iterator
-      erase_after(const_iterator __pos, iterator __last)
+      void
+      erase_after(const_iterator __pos, const_iterator __last)
       {
-        _Node_base* __tmp = __const_pointer_cast<_Node_base*>(__pos._M_node);
-        return iterator(this->_M_erase_after(__tmp, &*__last._M_node));
+        _Node_base* __tmpp = __const_pointer_cast<_Node_base*>(__pos._M_node);
+	_Node_base* __tmpl = __const_pointer_cast<_Node_base*>(__last._M_node);
+        this->_M_erase_after(__tmpp, __tmpl);
       }
 
       /**
@@ -1044,7 +1039,7 @@ _GLIBCXX_BEGIN_NAMESPACE(std)
        *  @brief  Insert element from another %forward_list.
        *  @param  pos  Iterator referencing the element to insert after.
        *  @param  list  Source list.
-       *  @param  it  Iterator referencing the element before the element
+       *  @param  i   Iterator referencing the element before the element
        *              to move.
        *
        *  Removes the element in list @a list referenced by @a i and
@@ -1052,10 +1047,14 @@ _GLIBCXX_BEGIN_NAMESPACE(std)
        */
       void
       splice_after(const_iterator __pos, forward_list&& __list,
-                   const_iterator __it)
+                   const_iterator __i)
       {
-	this->splice_after(__pos, std::forward<forward_list>(__list),
-			   __it, __it._M_next());
+	const_iterator __j = __i;
+	++__j;
+	if (__pos == __i || __pos == __j)
+	  return;
+
+	splice_after(__pos, std::move(__list), __i, __j);
       }
 
       /**
diff --git a/libstdc++-v3/include/bits/forward_list.tcc b/libstdc++-v3/include/bits/forward_list.tcc
index 1357369..1575cab 100644
--- a/libstdc++-v3/include/bits/forward_list.tcc
+++ b/libstdc++-v3/include/bits/forward_list.tcc
@@ -113,42 +113,34 @@ _GLIBCXX_BEGIN_NAMESPACE(std)
       }
 
   template<typename _Tp, typename _Alloc>
-    typename _Fwd_list_base<_Tp, _Alloc>::_Node_base::_Pointer
+    void
     _Fwd_list_base<_Tp, _Alloc>::
     _M_erase_after(typename _Node_base::_Pointer __pos)
     {
-      typename _Node::_Pointer __curr 
+      typename _Node::_Pointer __curr
         = __static_pointer_cast<typename _Node::_Pointer>(__pos->_M_next);
-      if (__curr)
-        {
-          typename _Node_base::_Pointer __next = __curr->_M_next;
-          __pos->_M_next = __next;
-          _M_get_Node_allocator().destroy(__curr);
-          _M_put_node(__curr);
-        }
-      return __pos;
+      __pos->_M_next = __curr->_M_next;
+      _M_get_Node_allocator().destroy(__curr);
+      _M_put_node(__curr);
     }
 
   template<typename _Tp, typename _Alloc>
-    typename _Fwd_list_base<_Tp, _Alloc>::_Node_base::_Pointer
+    void
     _Fwd_list_base<_Tp, _Alloc>::
     _M_erase_after(typename _Node_base::_Pointer __pos, 
                    typename _Node_base::_Pointer __last)
     {
       typename _Node::_Pointer __curr 
         = __static_pointer_cast<typename _Node::_Pointer>(__pos->_M_next);
-      while (__curr)
+      while (__curr != __last)
         {
           typename _Node::_Pointer __temp = __curr;
           __curr = __static_pointer_cast<typename _Node::_Pointer>
                                         (__curr->_M_next);
           _M_get_Node_allocator().destroy(__temp);
           _M_put_node(__temp);
-          __pos->_M_next = __curr;
-          if (__temp == __last)
-            break;
         }
-      return __pos;
+      __pos->_M_next = __last;
     }
   
   // Called by the range constructor to implement [23.1.1]/9
diff --git a/libstdc++-v3/testsuite/23_containers/forward_list/ext_pointer/modifiers/3.cc b/libstdc++-v3/testsuite/23_containers/forward_list/ext_pointer/modifiers/3.cc
index e27c3d7..5b43bbb 100644
--- a/libstdc++-v3/testsuite/23_containers/forward_list/ext_pointer/modifiers/3.cc
+++ b/libstdc++-v3/testsuite/23_containers/forward_list/ext_pointer/modifiers/3.cc
@@ -43,10 +43,7 @@ test01()
   ++pos;
   VERIFY(*pos == 1);
 
-  std::forward_list<int, _ExtPtr_allocator<int> >::iterator 
-    next = fl.erase_after(pos);
-
-  VERIFY(*next == 1);
+  fl.erase_after(pos);
 
   VERIFY(*pos == 1);
   ++pos;
@@ -78,14 +75,20 @@ test02()
   ++stop;
   VERIFY(*stop == 4);
 
-  std::forward_list<int, _ExtPtr_allocator<int> >::iterator 
-    next = fl.erase_after(pos, stop);
-
-  VERIFY(*next == 1);
+  fl.erase_after(pos, stop);
 
   VERIFY(*pos == 1);
   ++pos;
-  VERIFY(*pos == 5);
+  VERIFY(*pos == 4);
+  VERIFY(std::distance(fl.begin(), fl.end()) == 8);
+
+  fl.erase_after(pos, fl.end());
+  VERIFY(++pos == fl.end());
+  VERIFY(std::distance(fl.begin(), fl.end()) == 3);
+
+  fl.erase_after(fl.before_begin(), pos);
+  VERIFY(std::distance(fl.begin(), fl.end()) == 0);
+  VERIFY(fl.empty());
 }
 
 int
diff --git a/libstdc++-v3/testsuite/23_containers/forward_list/modifiers/3.cc b/libstdc++-v3/testsuite/23_containers/forward_list/modifiers/3.cc
index f15fae1..69163e0 100644
--- a/libstdc++-v3/testsuite/23_containers/forward_list/modifiers/3.cc
+++ b/libstdc++-v3/testsuite/23_containers/forward_list/modifiers/3.cc
@@ -37,8 +37,7 @@ test01()
   ++pos;
   VERIFY(*pos == 1);
 
-  std::forward_list<int>::iterator next = fl.erase_after(pos);
-  VERIFY(*next == 1);
+  fl.erase_after(pos);
 
   VERIFY(*pos == 1);
   ++pos;
@@ -65,12 +64,20 @@ test02()
   ++stop;
   VERIFY(*stop == 4);
 
-  std::forward_list<int>::iterator next = fl.erase_after(pos, stop);
-  VERIFY(*next == 1);
+  fl.erase_after(pos, stop);
 
   VERIFY(*pos == 1);
   ++pos;
-  VERIFY(*pos == 5);
+  VERIFY(*pos == 4);
+  VERIFY(std::distance(fl.begin(), fl.end()) == 8);
+
+  fl.erase_after(pos, fl.end());
+  VERIFY(++pos == fl.end());
+  VERIFY(std::distance(fl.begin(), fl.end()) == 3);
+
+  fl.erase_after(fl.before_begin(), pos);
+  VERIFY(std::distance(fl.begin(), fl.end()) == 0);
+  VERIFY(fl.empty());
 }
 
 int
diff --git a/libstdc++-v3/testsuite/23_containers/forward_list/requirements/dr438/assign_neg.cc b/libstdc++-v3/testsuite/23_containers/forward_list/requirements/dr438/assign_neg.cc
index 5062ddf..0d16771 100644
--- a/libstdc++-v3/testsuite/23_containers/forward_list/requirements/dr438/assign_neg.cc
+++ b/libstdc++-v3/testsuite/23_containers/forward_list/requirements/dr438/assign_neg.cc
@@ -1,6 +1,6 @@
 // { dg-do compile }
 // { dg-options "-std=gnu++0x" }
-// { dg-error "no matching" "" { target *-*-* } 1198 }
+// { dg-error "no matching" "" { target *-*-* } 1197 }
 // { dg-excess-errors "" }
 
 // Copyright (C) 2009 Free Software Foundation
diff --git a/libstdc++-v3/testsuite/23_containers/forward_list/requirements/dr438/constructor_1_neg.cc b/libstdc++-v3/testsuite/23_containers/forward_list/requirements/dr438/constructor_1_neg.cc
index 6347d96..d72b9fa 100644
--- a/libstdc++-v3/testsuite/23_containers/forward_list/requirements/dr438/constructor_1_neg.cc
+++ b/libstdc++-v3/testsuite/23_containers/forward_list/requirements/dr438/constructor_1_neg.cc
@@ -1,6 +1,6 @@
 // { dg-do compile }
 // { dg-options "-std=gnu++0x" }
-// { dg-error "no matching" "" { target *-*-* } 1198 }
+// { dg-error "no matching" "" { target *-*-* } 1197 }
 // { dg-excess-errors "" }
 
 // Copyright (C) 2009 Free Software Foundation
diff --git a/libstdc++-v3/testsuite/23_containers/forward_list/requirements/dr438/constructor_2_neg.cc b/libstdc++-v3/testsuite/23_containers/forward_list/requirements/dr438/constructor_2_neg.cc
index af66852..f0481a3 100644
--- a/libstdc++-v3/testsuite/23_containers/forward_list/requirements/dr438/constructor_2_neg.cc
+++ b/libstdc++-v3/testsuite/23_containers/forward_list/requirements/dr438/constructor_2_neg.cc
@@ -1,6 +1,6 @@
 // { dg-do compile }
 // { dg-options "-std=gnu++0x" }
-// { dg-error "no matching" "" { target *-*-* } 1198 }
+// { dg-error "no matching" "" { target *-*-* } 1197 }
 // { dg-excess-errors "" }
 
 // Copyright (C) 2009 Free Software Foundation
diff --git a/libstdc++-v3/testsuite/23_containers/forward_list/requirements/dr438/insert_neg.cc b/libstdc++-v3/testsuite/23_containers/forward_list/requirements/dr438/insert_neg.cc
index bc8a62d..c4a84ff 100644
--- a/libstdc++-v3/testsuite/23_containers/forward_list/requirements/dr438/insert_neg.cc
+++ b/libstdc++-v3/testsuite/23_containers/forward_list/requirements/dr438/insert_neg.cc
@@ -1,6 +1,6 @@
 // { dg-do compile }
 // { dg-options "-std=gnu++0x" }
-// { dg-error "no matching" "" { target *-*-* } 1198 }
+// { dg-error "no matching" "" { target *-*-* } 1197 }
 // { dg-excess-errors "" }
 
 // Copyright (C) 2009 Free Software Foundation