[Bug c++/60460] New: warn_unused_result doesn't warn on unused result when std::pair return type

[mdennis at merfer dot net]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60460

            Bug ID: 60460
           Summary: warn_unused_result doesn't warn on unused result when
                    std::pair return type
           Product: gcc
           Version: 4.8.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: mdennis at merfer dot net

possibly doesn't warn for any templated return type.

possibly related to 39808 and/or 47461.

see attached for repro.