[Bug libstdc++/51083] gnu++0x: resolving overloaded functions belonging to different namespaces

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51083

--- Comment #8 from Jonathan Wakely <redi at gcc dot gnu.org> 2011-11-10 
19:01:10 UTC ---
reduced

#include <complex>

namespace a
{
   template<typename> class Mat { };

typedef std::complex<double> cx_double;

typedef Mat<cx_double> cx_mat;

template<typename T>
  struct Mat2
  {
    Mat2(Mat<T>) { }
  };

struct Res { };

template<typename T>
  Res
  imag(Mat2<T>)
  {
    return Res();
  }

}

using namespace a;
using namespace std;

int main()
{
  cx_mat c;
  Res res = imag(c);
}


imag.cc: In function ‘int main()’:
imag.cc:34:19: error: conversion from
‘__gnu_cxx::__promote<a::Mat<std::complex<double> >, false>::__type {aka
a::Mat<std::complex<double> >}’ to non-scalar type ‘a::Res’ requested