[Bug c++/13967] [3.3?/3.4/3.5 regression] template template argument identifier lookup fails scoping rules

["gdr at integrable-solutions dot net" <gcc-bugzilla at gcc dot gnu dot org>]

------- Additional Comments From gdr at integrable-solutions dot net  2004-02-02 17:40 -------
Subject: Re:  [3.3?/3.4/3.5 regression] template template argument identifier lookup fails scoping rules

"gianni at mariani dot ws" <gcc-bugzilla@gcc.gnu.org> writes:

| Gabriel Dos Reis writes:
| |
| || So I'm confused as to what you mean "should be found".  Can you cite
| || the standard ? 
| |
| | What I meant is this:
| |
| |  struct X {
| |      int C;
| |
| |      template<class> void func(); 
| |  }; 
| |
| |
| |  template<class C>
| |    void X::func()
| |    {
| |       C c;     // ERROR: C is not a type.
| |    }
| |
| | In the definition of X::func(), lookup for C will find X::C instead of
| | the template parameter. 
| 
| Yes - but is this the behaviour as specified in the standard ? 

I just checked with the Core group and John Spicer recalled that the
committee madethe general decision that a class-member hides a
template-parameter. See the implementation of that decision in
14.6.1/5 and 14.6.1/7.  

| At first glance, it seems like the gcc behaviour is probably wrong.

But, GCC behaviour is Right :-)

The fundamental issue is that template-parameters can be renamed and
you don't want to depend on that.  Consider

   template<class T>
      struct X {  
         struct B { };
  
         void f();
      };

   template<class B>
      void  X<B>::f()
      { 
         B* p = 0;      // 'B' is X<>::B, not the template parameter
      }

-- Gaby


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13967