[Bug libstdc++/57283] New: missing typedefs in specialized std::mem_fn for member variables

[record.nctu.cis91 at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57283

            Bug ID: 57283
           Summary: missing typedefs in specialized std::mem_fn for member
                    variables
           Product: gcc
           Version: 4.7.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: record.nctu.cis91 at gmail dot com

Created attachment 30118
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=30118&action=edit
code-reproduce-this-issue.cpp

I found that gcc complain that "no type named ‘argument_type’ in ‘class
std::_Mem_fn<int cls::*>’", with the code in attachment.

Then I try to locate the problem and find there is no any typedefs for
argument_type.
So I guess it's missing the required typedefs.