[Bug c++/11744] New: Wrong namespace lookup when induced by a template parameter

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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=11744

           Summary: Wrong namespace lookup when induced by a template
                    parameter
           Product: gcc
           Version: 3.4
            Status: UNCONFIRMED
          Severity: critical
          Priority: P2
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: nicolas dot burrus at lrde dot epita dot fr
                CC: gcc-bugs at gcc dot gnu dot org
 GCC build triplet: i686-pc-linux-gnu
  GCC host triplet: i686-pc-linux-gnu
GCC target triplet: i686-pc-linux-gnu

Considering the following code:

namespace nsp_foo {

  struct A {};

  struct foo {};

}

namespace nsp_bar {

  void foo(nsp_foo::A) {}

  template <class T>
  void bar(T t)
  {
    nsp_bar::foo(t); // line 16
  }

}

int main()
{
  nsp_bar::bar(nsp_foo::A());
}

Here is g++-3.4 output:

namespaces.cc: In function `void nsp_bar::bar(T) [with T = nsp_foo::A]':
namespaces.cc:23:   instantiated from here
namespaces.cc:5: error: `struct nsp_foo::foo' is not a function,
namespaces.cc:11: error:   conflict with `void nsp_bar::foo(nsp_foo::A)'
namespaces.cc:16: error:   in call to `foo'

This would be normal if line 16 was a call to "foo(t)" without
namespace prefix, as koenig lookup is done in the namespace of
template parameters. But using of the "nsp_bar::" prefix, the call to
foo should not be ambiguous. g++-3.3, como and icc accept this code.

It works correctly if bar is non template "void bar(nsp_foo::A)".

Environment:
System: Linux ouagadougou 2.4.21 #1 Fri Jul 25 11:19:01 CEST 2003 i686 GNU/Linux
Architecture: i686

	
host: i686-pc-linux-gnu
build: i686-pc-linux-gnu
target: i686-pc-linux-gnu
configured with: ../../lrde/ext/gcc/configure --prefix=/home/lrde/lrde/usr/gcc-3.4 --enable-languages=c,c++ : (reconfigured)  : (reconfigured) ../../lrde/ext/gcc/configure --enable-languages=c,c++ --prefix=/home/lrde/lrde/usr/gcc-3.4 : (reconfigured) ../../lrde/ext/gcc/configure --enable-languages=c,c++ --prefix=/home/lrde/lrde/usr/gcc-3.4 : (reconfigured)  : (reconfigured) /home/lrde/stud/burrus_n/work/lrde/ext/gcc/configure --prefix=~lrde/usr/gcc-3.4 --enable-languages=c,c++ : (reconfigured) /home/lrde/stud/burrus_n/work/lrde/ext/gcc/configure --prefix=~lrde/usr/gcc-3.4 --enable-languages=c,c++ : (reconfigured) /home/lrde/stud/burrus_n/work/lrde/ext/gcc/configure --prefix=~lrde/usr/gcc-3.4 --enable-languages=c,c++ : (reconfigured) /home/lrde/stud/burrus_n/work/lrde/ext/gcc/configure --prefix=/home/lrde/lrde/usr/gcc-3.4 --enable-languages=c,c++

How-To-Repeat:
	Compile the given code.