[Bug c++/11870] New: Namespace lookup failure. Inside a function of a class in a namespace, a >> b does not look ::operator>>(a, b) if an operator>> of the same namespace is declared as friend.

["lachaume at mpifr-bonn dot mpg dot de" <gcc-bugzilla at gcc dot gnu dot org>]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=11870

           Summary: Namespace lookup failure.  Inside a function of a class
                    in a namespace, a >> b does not look ::operator>>(a, b)
                    if an operator>> of the same namespace is declared as
                    friend.
           Product: gcc
           Version: 3.3.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: lachaume at mpifr-bonn dot mpg dot de
                CC: gcc-bugs at gcc dot gnu dot org
 GCC build triplet: /homes/lachaume/src/gcc-3.3.1/configure --with-gcc-
                    version-trigg
  GCC host triplet: Linux pc179 2.4.10-4GB #1 Tue Feb 12 14:25:31 MET 2002
                    i686 unkn

The following code is unexpectedly rejected:

   namespace N {

      class I { };
      class V { };
      I in;

   }

   N::I& operator >> (N::I& i, N::V&) { return i; }  

   namespace M {

      struct S {
         static N::V f() {   N::V t;   N::in >> t;   return t;  }
         friend N::I& operator >> (N::I&, S&);
      };

   }

   int main() { M::S::f(); }

The output is of g++ -Wall is

   bug.cpp: In static member function `static N::V M::S::f()':
   bug.cpp:14: error: no match for 'operator>>' in 'N::in >> t'
   bug.cpp:15: error: candidates are: I& M::operator>>(N::I&, M::S&)

It compiles perfectly without the friend declaration.  It is also OK
if the friend declaration is
   friend N::I& ::operator >> (N::I&, S&);

The same problem arises in prior versions of gcc (2.95.3) on the same system &
host.