[PATCH] Add priority_queue::value_compare (LWG 2684)

[Jonathan Wakely]

        * include/bits/stl_queue.h (priority_queue::value_compare): Define.

This is only Tentatively Ready but I don't think there's any harm in
making the change now. Libc++ have been shipping this for years,
without realising it wasn't actually in the standard :-)

Tested x86_64, committed to trunk.


commit 64c647342c0786ae01b4f0b4b4ce716da7faa757
Author: redi <redi@138bc75d-0d04-0410-961f-82ee72b054a4>
Date:   Tue May 24 15:59:05 2016 +0000

    Add priority_queue::value_compare (LWG 2684)
    
        * include/bits/stl_queue.h (priority_queue::value_compare): Define.
    
    git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@236646 
138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/libstdc++-v3/include/bits/stl_queue.h 
b/libstdc++-v3/include/bits/stl_queue.h
index 9caca03..a292309 100644
--- a/libstdc++-v3/include/bits/stl_queue.h
+++ b/libstdc++-v3/include/bits/stl_queue.h
@@ -417,6 +417,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       typedef typename _Sequence::const_reference           const_reference;
       typedef typename _Sequence::size_type                 size_type;
       typedef          _Sequence                            container_type;
+      // _GLIBCXX_RESOLVE_LIB_DEFECTS
+      // DR 2684. priority_queue lacking comparator typedef
+      typedef         _Compare                             value_compare;
 
     protected:
       //  See queue::c for notes on these names.