2003-11-11 Doug Gregor <gregod@cs.rpi.edu>

	* docs/html/debug.html: Document libstdc++ debug mode.
	* docs/html/debug_mode.html: Document libstdc++ debug mode design.
	* docs/html/test.html: Document how to test under debug mode.
	* docs/html/17_intro/howto.html: Document debug-mode macros.
	* include/Makefile.am: Install debug-mode headers.
	* src/Makefile.am: Include debug.cc.
	* include/bits/basic_string.tcc:
	  (basic_string::_S_construct): Fix NULL pointer check.
	  (__is_null_pointer): New.
	  Add precondition annotations.
	* include/bits/stream_iterator.h (istream_iterator,
	ostream_iterator): Added precondition annotations.
	* include/bits/streambuf_iterator.h (istreambuf_iterator): Ditto.
	* include/bits/stl_queue.h (queue, priority_queue): Ditto.
	* include/bits/stl_stack.h (stack): Ditto.
	* include/bits/basic_string.h (basic_string): Ditto.
	* include/bits/basic_string.tcc (basic_string): Ditto.
	* include/std/std_memory.h (auto_ptr): Ditto.
	* include/std/std_valarray.h (valarray): Ditto.
	* include/bits/stl_algo.h: Added algorithm precondition
	annotations.
	* include/bits/stl_algobase.h: Added algorithm precondition
	annotations.
	* include/bits/stl_numeric.h: Ditto.
	* include/ext/algorithm: Added algorithm precondition
	annotations.
	(__is_heap): Moved away from here.
	* include/bits/stl_heap.h: Added algorithm precondition
	annotations.
	(__is_heap): Moved to the top of this file.
	(__is_heap): Added iterator range overloads.
	* testsuite/20_util/auto_ptr_neg.cc: Fix line numbers to match up
	with changes in std_memory.h.
	* testsuite/23_containers/list/operators/4.cc: Don't verify
	performance guarantees when in debug mode.
	* testsuite/23_containers/bitset/invalidation/1.cc: New.
	* testsuite/23_containers/deque/invalidation/1.cc: New.
	* testsuite/23_containers/deque/invalidation/2.cc: New.
	* testsuite/23_containers/deque/invalidation/3.cc: New.
	* testsuite/23_containers/deque/invalidation/4.cc: New.
	* testsuite/23_containers/list/invalidation/1.cc: New.
	* testsuite/23_containers/list/invalidation/2.cc: New.
	* testsuite/23_containers/list/invalidation/3.cc: New.
	* testsuite/23_containers/list/invalidation/4.cc: New.
	* testsuite/23_containers/map/invalidation/1.cc: New.
	* testsuite/23_containers/map/invalidation/2.cc: New.
	* testsuite/23_containers/multimap/invalidation/1.cc: New.
	* testsuite/23_containers/multimap/invalidation/2.cc: New.
	* testsuite/23_containers/multiset/invalidation/1.cc: New.
	* testsuite/23_containers/multiset/invalidation/2.cc: New.
	* testsuite/23_containers/set/invalidation/1.cc: New.
	* testsuite/23_containers/set/invalidation/2.cc: New.
	* testsuite/23_containers/vector/invalidation/1.cc: New.
	* testsuite/23_containers/vector/invalidation/2.cc: New.
	* testsuite/23_containers/vector/invalidation/3.cc: New.
	* testsuite/23_containers/vector/invalidation/4.cc: New.
	* testsuite/25_algorithms/heap.cc: Don't verify
	performance guarantees when in debug mode.
	* include/debug/bitset: New.
	* include/debug/debug.h: New.
	* include/debug/deque: New.
	* include/debug/formatter.h: New.
	* include/debug/hash_map: New.
	* include/debug/hash_map.h: New.
	* include/debug/hash_multimap.h: New.
	* include/debug/hash_set: New.
	* include/debug/hash_set.h: New.
	* include/debug/hash_multiset.h: New.
	* include/debug/list: New.
	* include/debug/map: New.
	* include/debug/map.h: New.
	* include/debug/multimap.h: New.
	* include/debug/multiset.h: New.
	* include/debug/safe_base.h: New.
	* include/debug/safe_iterator.h: New.
	* include/debug/safe_iterator.tcc: New.
	* include/debug/safe_sequence.h: New.
	* include/debug/set: New.
	* include/debug/set.h: New.
	* include/debug/string: New.
	* include/debug/vector: New.
	* src/debug.cc: New.
	* config/linker-map.gnu: Add debug mode symbols.

2003-11-11  Benjamin Kosnik  <bkoz@redhat.com>

	* src/string-inst.cc: Tweak namespaces.
	* src/misc-inst.cc: Same.
	* docs/html/debug.html: Edits.
	* config/link-map.gnu: Remove cruft.

	* include/bits/c++config: Add in namespace associations.
	* include/std/std_bitset.h: Adjust namespace to __gnu_norm,
	comment tweaks.
	* include/bits/deque.tcc: Same.
	* include/bits/list.tcc: Same.
	* include/bits/stl_bvector.h: Same.
	* include/bits/stl_deque.h: Same.
	* include/bits/stl_list.h: Same.
	* include/bits/stl_map.h: Same.
	* include/bits/stl_multimap.h: Same.
	* include/bits/stl_multiset.h: Same.
	* include/bits/stl_set.h: Same.
	* include/bits/stl_vector.h: Same.
	* include/bits/vector.tcc: Same.

	* include/std/std_algorithm.h: Remove markup comments.
	* include/std/std_functional.h: Same.
	* include/std/std_iterator.h: Same.
	* include/std/std_numeric.h: Same.
	* include/std/std_utility.h: Same.
	* include/bits/stl_queue.h: Formatting tweaks.
	* include/bits/stl_stack.h: Same.
	* include/std/std_deque.h: Include debugging version in debug mode.
	* include/std/std_list.h: Same.
	* include/std/std_map.h: Same.
	* include/std/std_set.h: Same.
	* include/std/std_vector.h: Same.
	* include/std/std_queue.h: Use deque, vector.
	* include/std/std_stack.h: Same.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@73459 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 290 insertions, 250 deletions

diff --git a/libstdc++-v3/include/bits/stl_queue.h b/libstdc++-v3/include/bits/stl_queue.h
index 0bb41acaf9f..441fc55ef4b 100644
--- a/libstdc++-v3/include/bits/stl_queue.h
+++ b/libstdc++-v3/include/bits/stl_queue.h
@@ -62,20 +62,21 @@
 #define _QUEUE_H 1
 
 #include <bits/concept_check.h>
+#include <debug/debug.h>
 
 namespace std
 {
   // Forward declarations of operators < and ==, needed for friend declaration.
+  template<typename _Tp, typename _Sequence = deque<_Tp> >
+    class queue;
   
-  template <typename _Tp, typename _Sequence = deque<_Tp> >
-  class queue;
-  
-  template <typename _Tp, typename _Seq>
-  inline bool operator==(const queue<_Tp,_Seq>&, const queue<_Tp,_Seq>&);
-  
-  template <typename _Tp, typename _Seq>
-  inline bool operator<(const queue<_Tp,_Seq>&, const queue<_Tp,_Seq>&);
+  template<typename _Tp, typename _Seq>
+    inline bool 
+    operator==(const queue<_Tp,_Seq>&, const queue<_Tp,_Seq>&);
   
+  template<typename _Tp, typename _Seq>
+    inline bool 
+    operator<(const queue<_Tp,_Seq>&, const queue<_Tp,_Seq>&);
   
   /**
    *  @brief  A standard container giving FIFO behavior.
@@ -101,111 +102,133 @@ namespace std
    *  which is a typedef for the second Sequence parameter, and @c push and
    *  @c pop, which are standard %queue/FIFO operations.
   */
-  template <typename _Tp, typename _Sequence>
+  template<typename _Tp, typename _Sequence>
     class queue
-  {
-    // concept requirements
-    typedef typename _Sequence::value_type _Sequence_value_type;
-    __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
-    __glibcxx_class_requires(_Sequence, _FrontInsertionSequenceConcept)
-    __glibcxx_class_requires(_Sequence, _BackInsertionSequenceConcept)
-    __glibcxx_class_requires2(_Tp, _Sequence_value_type, _SameTypeConcept)
-  
-    template <typename _Tp1, typename _Seq1>
-    friend bool operator== (const queue<_Tp1, _Seq1>&,
-                            const queue<_Tp1, _Seq1>&);
-    template <typename _Tp1, typename _Seq1>
-    friend bool operator< (const queue<_Tp1, _Seq1>&,
-                           const queue<_Tp1, _Seq1>&);
-  
-  public:
-    typedef typename _Sequence::value_type                value_type;
-    typedef typename _Sequence::reference                 reference;
-    typedef typename _Sequence::const_reference           const_reference;
-    typedef typename _Sequence::size_type                 size_type;
-    typedef          _Sequence                            container_type;
-  
-  protected:
-    /**
-     *  'c' is the underlying container.  Maintainers wondering why this isn't
-     *  uglified as per style guidelines should note that this name is
-     *  specified in the standard, [23.2.3.1].  (Why?  Presumably for the same
-     *  reason that it's protected instead of private:  to allow derivation.
-     *  But none of the other containers allow for derivation.  Odd.)
-    */
-    _Sequence c;
-  
-  public:
-    /**
-     *  @brief  Default constructor creates no elements.
-    */
-    explicit
-    queue(const _Sequence& __c = _Sequence())
-    : c(__c) {}
-  
-    /**
-     *  Returns true if the %queue is empty.
-    */
-    bool
-    empty() const { return c.empty(); }
-  
-    /**  Returns the number of elements in the %queue.  */
-    size_type
-    size() const { return c.size(); }
-  
-    /**
-     *  Returns a read/write reference to the data at the first element of the
-     *  %queue.
-    */
-    reference
-    front() { return c.front(); }
-  
-    /**
-     *  Returns a read-only (constant) reference to the data at the first
-     *  element of the %queue.
-    */
-    const_reference
-    front() const { return c.front(); }
-  
-    /**
-     *  Returns a read/write reference to the data at the last element of the
-     *  %queue.
-    */
-    reference
-    back() { return c.back(); }
-  
-    /**
-     *  Returns a read-only (constant) reference to the data at the last
-     *  element of the %queue.
-    */
-    const_reference
-    back() const { return c.back(); }
-  
-    /**
-     *  @brief  Add data to the end of the %queue.
-     *  @param  x  Data to be added.
-     *
-     *  This is a typical %queue operation.  The function creates an element at
-     *  the end of the %queue and assigns the given data to it.
-     *  The time complexity of the operation depends on the underlying
-     *  sequence.
-    */
-    void
-    push(const value_type& __x) { c.push_back(__x); }
-  
-    /**
-     *  @brief  Removes first element.
-     *
-     *  This is a typical %queue operation.  It shrinks the %queue by one.
-     *  The time complexity of the operation depends on the underlying
-     *  sequence.
-     *
-     *  Note that no data is returned, and if the first element's data is
-     *  needed, it should be retrieved before pop() is called.
-    */
-    void
-    pop() { c.pop_front(); }
-  };
+    {
+      // concept requirements
+      typedef typename _Sequence::value_type _Sequence_value_type;
+      __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
+      __glibcxx_class_requires(_Sequence, _FrontInsertionSequenceConcept)
+      __glibcxx_class_requires(_Sequence, _BackInsertionSequenceConcept)
+      __glibcxx_class_requires2(_Tp, _Sequence_value_type, _SameTypeConcept)
+  
+	template<typename _Tp1, typename _Seq1>
+          friend bool 
+          operator==(const queue<_Tp1, _Seq1>&, const queue<_Tp1, _Seq1>&);
+
+      template<typename _Tp1, typename _Seq1>
+        friend bool 
+        operator<(const queue<_Tp1, _Seq1>&, const queue<_Tp1, _Seq1>&);
+  
+    public:
+      typedef typename _Sequence::value_type                value_type;
+      typedef typename _Sequence::reference                 reference;
+      typedef typename _Sequence::const_reference           const_reference;
+      typedef typename _Sequence::size_type                 size_type;
+      typedef          _Sequence                            container_type;
+      
+    protected:
+      /**
+       *  'c' is the underlying container.  Maintainers wondering why
+       *  this isn't uglified as per style guidelines should note that
+       *  this name is specified in the standard, [23.2.3.1].  (Why?
+       *  Presumably for the same reason that it's protected instead
+       *  of private: to allow derivation.  But none of the other
+       *  containers allow for derivation.  Odd.)
+       */
+      _Sequence c;
+      
+    public:
+      /**
+       *  @brief  Default constructor creates no elements.
+       */
+      explicit
+      queue(const _Sequence& __c = _Sequence()) : c(__c) {}
+      
+      /**
+       *  Returns true if the %queue is empty.
+       */
+      bool
+      empty() const { return c.empty(); }
+      
+      /**  Returns the number of elements in the %queue.  */
+      size_type
+      size() const { return c.size(); }
+      
+      /**
+       *  Returns a read/write reference to the data at the first
+       *  element of the %queue.
+       */
+      reference
+      front() 
+      { 
+	__glibcxx_requires_nonempty();
+	return c.front(); 
+      }
+      
+      /**
+       *  Returns a read-only (constant) reference to the data at the first
+       *  element of the %queue.
+       */
+      const_reference
+      front() const 
+      { 
+	__glibcxx_requires_nonempty();
+	return c.front(); 
+      }
+      
+      /**
+       *  Returns a read/write reference to the data at the last
+       *  element of the %queue.
+       */
+      reference
+      back() 
+      {
+	__glibcxx_requires_nonempty();
+	return c.back(); 
+      }
+      
+      /**
+       *  Returns a read-only (constant) reference to the data at the last
+       *  element of the %queue.
+       */
+      const_reference
+      back() const 
+      {
+	__glibcxx_requires_nonempty();
+	return c.back(); 
+      }
+      
+      /**
+       *  @brief  Add data to the end of the %queue.
+       *  @param  x  Data to be added.
+       *
+       *  This is a typical %queue operation.  The function creates an
+       *  element at the end of the %queue and assigns the given data
+       *  to it.  The time complexity of the operation depends on the
+       *  underlying sequence.
+       */
+      void
+      push(const value_type& __x) { c.push_back(__x); }
+      
+      /**
+       *  @brief  Removes first element.
+       *
+       *  This is a typical %queue operation.  It shrinks the %queue by one.
+       *  The time complexity of the operation depends on the underlying
+       *  sequence.
+       *
+       *  Note that no data is returned, and if the first element's
+       *  data is needed, it should be retrieved before pop() is
+       *  called.
+       */
+      void
+      pop() 
+      { 
+	__glibcxx_requires_nonempty();
+	c.pop_front(); 
+      }
+    };
   
   
   /**
@@ -219,9 +242,10 @@ namespace std
    *  linear in the size of the sequences, and queues are considered equivalent
    *  if their sequences compare equal.
   */
-  template <typename _Tp, typename _Sequence>
+  template<typename _Tp, typename _Sequence>
     inline bool 
-    operator==(const queue<_Tp,_Sequence>& __x, const queue<_Tp,_Sequence>& __y)
+    operator==(const queue<_Tp,_Sequence>& __x, 
+	       const queue<_Tp,_Sequence>& __y)
     { return __x.c == __y.c; }
   
   /**
@@ -230,39 +254,43 @@ namespace std
    *  @param  y  A %queue of the same type as @a x.
    *  @return  True iff @a x is lexicographically less than @a y.
    *
-   *  This is an total ordering relation.  Complexity and semantics depend on
-   *  the underlying sequence type, but the expected rules are:  this relation
-   *  is linear in the size of the sequences, the elements must be comparable
-   *  with @c <, and std::lexicographical_compare() is usually used to make the
+   *  This is an total ordering relation.  Complexity and semantics
+   *  depend on the underlying sequence type, but the expected rules
+   *  are: this relation is linear in the size of the sequences, the
+   *  elements must be comparable with @c <, and
+   *  std::lexicographical_compare() is usually used to make the
    *  determination.
   */
-  template <typename _Tp, typename _Sequence>
+  template<typename _Tp, typename _Sequence>
     inline bool
     operator<(const queue<_Tp,_Sequence>& __x, const queue<_Tp,_Sequence>& __y)
     { return __x.c < __y.c; }
   
   /// Based on operator==
-  template <typename _Tp, typename _Sequence>
+  template<typename _Tp, typename _Sequence>
     inline bool
-    operator!=(const queue<_Tp,_Sequence>& __x, const queue<_Tp,_Sequence>& __y)
+    operator!=(const queue<_Tp,_Sequence>& __x, 
+	       const queue<_Tp,_Sequence>& __y)
     { return !(__x == __y); }
   
   /// Based on operator<
-  template <typename _Tp, typename _Sequence>
+  template<typename _Tp, typename _Sequence>
     inline bool 
     operator>(const queue<_Tp,_Sequence>& __x, const queue<_Tp,_Sequence>& __y)
     { return __y < __x; }
   
   /// Based on operator<
-  template <typename _Tp, typename _Sequence>
+  template<typename _Tp, typename _Sequence>
     inline bool 
-    operator<=(const queue<_Tp,_Sequence>& __x, const queue<_Tp,_Sequence>& __y)
+    operator<=(const queue<_Tp,_Sequence>& __x, 
+	       const queue<_Tp,_Sequence>& __y)
     { return !(__y < __x); }
   
   /// Based on operator<
-  template <typename _Tp, typename _Sequence>
+  template<typename _Tp, typename _Sequence>
     inline bool 
-    operator>=(const queue<_Tp,_Sequence>& __x, const queue<_Tp,_Sequence>& __y)
+    operator>=(const queue<_Tp,_Sequence>& __x, 
+	       const queue<_Tp,_Sequence>& __y)
     { return !(__x < __y); }
   
   
@@ -272,157 +300,169 @@ namespace std
    *  @ingroup Containers
    *  @ingroup Sequences
    *
-   *  This is not a true container, but an @e adaptor.  It holds another
-   *  container, and provides a wrapper interface to that container.  The
-   *  wrapper is what enforces sorting and first-in-first-out %queue behavior.
-   *  Very few of the standard container/sequence interface requirements are
-   *  met (e.g., iterators).
+   *  This is not a true container, but an @e adaptor.  It holds
+   *  another container, and provides a wrapper interface to that
+   *  container.  The wrapper is what enforces sorting and
+   *  first-in-first-out %queue behavior.  Very few of the standard
+   *  container/sequence interface requirements are met (e.g.,
+   *  iterators).
    *
    *  The second template parameter defines the type of the underlying
-   *  sequence/container.  It defaults to std::vector, but it can be any type
-   *  that supports @c front(), @c push_back, @c pop_back, and random-access
-   *  iterators, such as std::deque or an appropriate user-defined type.
+   *  sequence/container.  It defaults to std::vector, but it can be
+   *  any type that supports @c front(), @c push_back, @c pop_back,
+   *  and random-access iterators, such as std::deque or an
+   *  appropriate user-defined type.
    *
-   *  The third template parameter supplies the means of making priority
-   *  comparisons.  It defaults to @c less<value_type> but can be anything
-   *  defining a strict weak ordering.
+   *  The third template parameter supplies the means of making
+   *  priority comparisons.  It defaults to @c less<value_type> but
+   *  can be anything defining a strict weak ordering.
    *
    *  Members not found in "normal" containers are @c container_type,
-   *  which is a typedef for the second Sequence parameter, and @c push,
-   *  @c pop, and @c top, which are standard %queue/FIFO operations.
+   *  which is a typedef for the second Sequence parameter, and @c
+   *  push, @c pop, and @c top, which are standard %queue/FIFO
+   *  operations.
    *
-   *  @note  No equality/comparison operators are provided for %priority_queue.
+   *  @note No equality/comparison operators are provided for
+   *  %priority_queue.
    *
-   *  @note  Sorting of the elements takes place as they are added to, and
-   *         removed from, the %priority_queue using the %priority_queue's
-   *         member functions.  If you access the elements by other means, and
-   *         change their data such that the sorting order would be different,
-   *         the %priority_queue will not re-sort the elements for you.  (How
-   *         could it know to do so?)
+   *  @note Sorting of the elements takes place as they are added to,
+   *  and removed from, the %priority_queue using the
+   *  %priority_queue's member functions.  If you access the elements
+   *  by other means, and change their data such that the sorting
+   *  order would be different, the %priority_queue will not re-sort
+   *  the elements for you.  (How could it know to do so?)
   */
-  template <typename _Tp, typename _Sequence = vector<_Tp>,
+  template<typename _Tp, typename _Sequence = vector<_Tp>,
             typename _Compare  = less<typename _Sequence::value_type> >
     class priority_queue
-  {
-    // concept requirements
-    typedef typename _Sequence::value_type _Sequence_value_type;
-    __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
-    __glibcxx_class_requires(_Sequence, _SequenceConcept)
-    __glibcxx_class_requires(_Sequence, _RandomAccessContainerConcept)
-    __glibcxx_class_requires2(_Tp, _Sequence_value_type, _SameTypeConcept)
-    __glibcxx_class_requires4(_Compare, bool, _Tp, _Tp, _BinaryFunctionConcept)
-  
-  public:
-    typedef typename _Sequence::value_type                value_type;
-    typedef typename _Sequence::reference                 reference;
-    typedef typename _Sequence::const_reference           const_reference;
-    typedef typename _Sequence::size_type                 size_type;
-    typedef          _Sequence                            container_type;
-  
-  protected:
-    //  See queue::c for notes on these names.
-    _Sequence  c;
-    _Compare   comp;
-  
-  public:
-    /**
-     *  @brief  Default constructor creates no elements.
-    */
-    explicit
-    priority_queue(const _Compare& __x = _Compare(),
-                   const _Sequence& __s = _Sequence()) 
-    : c(__s), comp(__x) 
-    { std::make_heap(c.begin(), c.end(), comp); }
-  
-    /**
-     *  @brief  Builds a %queue from a range.
-     *  @param  first  An input iterator.
-     *  @param  last  An input iterator.
-     *  @param  x  A comparison functor describing a strict weak ordering.
-     *  @param  s  An initial sequence with which to start.
-     * 
-     *  Begins by copying @a s, inserting a copy of the elements from
-     *  @a [first,last) into the copy of @a s, then ordering the copy
-     *  according to @a x.
-     *
-     *  For more information on function objects, see the documentation on
-     *  @link s20_3_1_base functor base classes@endlink.
-    */
-    template <typename _InputIterator>
-      priority_queue(_InputIterator __first, _InputIterator __last,
-                     const _Compare& __x = _Compare(),
-                     const _Sequence& __s = _Sequence())
-      : c(__s), comp(__x)
-      { 
-        c.insert(c.end(), __first, __last);
-        std::make_heap(c.begin(), c.end(), comp);
-      }
-  
-    /**
-     *  Returns true if the %queue is empty.
-    */
-    bool
-    empty() const { return c.empty(); }
-  
-    /**  Returns the number of elements in the %queue.  */
-    size_type
-    size() const { return c.size(); }
-  
-    /**
-     *  Returns a read-only (constant) reference to the data at the first
-     *  element of the %queue.
-    */
-    const_reference
-    top() const { return c.front(); }
-  
-    /**
-     *  @brief  Add data to the %queue.
-     *  @param  x  Data to be added.
-     *
-     *  This is a typical %queue operation.
-     *  The time complexity of the operation depends on the underlying
-     *  sequence.
-    */
-    void 
-    push(const value_type& __x) 
     {
-      try 
+      // concept requirements
+      typedef typename _Sequence::value_type _Sequence_value_type;
+      __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
+      __glibcxx_class_requires(_Sequence, _SequenceConcept)
+      __glibcxx_class_requires(_Sequence, _RandomAccessContainerConcept)
+      __glibcxx_class_requires2(_Tp, _Sequence_value_type, _SameTypeConcept)
+      __glibcxx_class_requires4(_Compare, bool, _Tp,_Tp,_BinaryFunctionConcept)
+  
+	public:
+      typedef typename _Sequence::value_type                value_type;
+      typedef typename _Sequence::reference                 reference;
+      typedef typename _Sequence::const_reference           const_reference;
+      typedef typename _Sequence::size_type                 size_type;
+      typedef          _Sequence                            container_type;
+      
+    protected:
+      //  See queue::c for notes on these names.
+      _Sequence  c;
+      _Compare   comp;
+      
+    public:
+      /**
+       *  @brief  Default constructor creates no elements.
+       */
+      explicit
+      priority_queue(const _Compare& __x = _Compare(), 
+		     const _Sequence& __s = _Sequence()) 
+      : c(__s), comp(__x) 
+      { std::make_heap(c.begin(), c.end(), comp); }
+  
+      /**
+       *  @brief  Builds a %queue from a range.
+       *  @param  first  An input iterator.
+       *  @param  last  An input iterator.
+       *  @param  x  A comparison functor describing a strict weak ordering.
+       *  @param  s  An initial sequence with which to start.
+       * 
+       *  Begins by copying @a s, inserting a copy of the elements
+       *  from @a [first,last) into the copy of @a s, then ordering
+       *  the copy according to @a x.
+       *
+       *  For more information on function objects, see the
+       *  documentation on @link s20_3_1_base functor base
+       *  classes@endlink.
+       */
+      template<typename _InputIterator>
+        priority_queue(_InputIterator __first, _InputIterator __last,
+		       const _Compare& __x = _Compare(),
+		       const _Sequence& __s = _Sequence())
+	: c(__s), comp(__x)
+        { 
+	  __glibcxx_requires_valid_range(__first, __last);
+	  c.insert(c.end(), __first, __last);
+	  std::make_heap(c.begin(), c.end(), comp);
+	}
+      
+      /**
+       *  Returns true if the %queue is empty.
+       */
+      bool
+      empty() const { return c.empty(); }
+      
+      /**  Returns the number of elements in the %queue.  */
+      size_type
+      size() const { return c.size(); }
+      
+      /**
+       *  Returns a read-only (constant) reference to the data at the first
+       *  element of the %queue.
+       */
+      const_reference
+      top() const 
+      {
+	__glibcxx_requires_nonempty();
+	return c.front(); 
+      }
+      
+      /**
+       *  @brief  Add data to the %queue.
+       *  @param  x  Data to be added.
+       *
+       *  This is a typical %queue operation.
+       *  The time complexity of the operation depends on the underlying
+       *  sequence.
+       */
+      void 
+      push(const value_type& __x) 
+      {
+	try 
         {
           c.push_back(__x); 
           std::push_heap(c.begin(), c.end(), comp);
         }
-      catch(...)
+	catch(...)
         {
           c.clear();
           __throw_exception_again; 
         }
-    }
-  
-    /**
-     *  @brief  Removes first element.
-     *
-     *  This is a typical %queue operation.  It shrinks the %queue by one.
-     *  The time complexity of the operation depends on the underlying
-     *  sequence.
-     *
-     *  Note that no data is returned, and if the first element's data is
-     *  needed, it should be retrieved before pop() is called.
-    */
-    void 
-    pop() 
-    {
-      try 
+      }
+      
+      /**
+       *  @brief  Removes first element.
+       *
+       *  This is a typical %queue operation.  It shrinks the %queue
+       *  by one.  The time complexity of the operation depends on the
+       *  underlying sequence.
+       *
+       *  Note that no data is returned, and if the first element's
+       *  data is needed, it should be retrieved before pop() is
+       *  called.
+       */
+      void 
+      pop() 
+      {
+	__glibcxx_requires_nonempty();
+	try 
         {
           std::pop_heap(c.begin(), c.end(), comp);
           c.pop_back();
         }
-      catch(...)
+	catch(...)
         {
           c.clear();
           __throw_exception_again; 
         }
-    }
-  };
+      }
+    };
   
   // No equality/comparison operators are provided for priority_queue.
 } // namespace std