c++/8753: Wishlist: g++ disable Warning "is implicitly a typename"

[Steffen Neumann <sneumann at TechFak dot Uni-Bielefeld dot DE>]

>Number:         8753
>Category:       c++
>Synopsis:       Wishlist: g++ disable Warning "is implicitly a typename"
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    unassigned
>State:          open
>Class:          change-request
>Submitter-Id:   net
>Arrival-Date:   Fri Nov 29 05:16:00 PST 2002
>Closed-Date:
>Last-Modified:
>Originator:     
>Release:        3.1
>Organization:
Uni Bielefeld, Technical Faculty
>Environment:
System: OSF1 liszt V4.0 1229 alpha
Machine: alpha
host: alpha-dec-osf4.0f
build: alpha-dec-osf4.0f
target: alpha-dec-osf4.0f
configured with: /vol/gnu/src/gcc/gcc-3.1-branch-dist/configure --prefix=/vol/gnu --with-local-prefix=/vol/gnu --disable-nls alpha-dec-osf4.0f
>Description:

        The C++ Standard requires that typedef'ed 
        template types be marked with 'typename ...'.

        Old Code therefore emits tons of warnings for which 
        no -Wno-implicit-... switch exists.

        If it doesn't clash with some gcc policy,
        I'd like to ask for an '-Wno-implicit-typename' 
        switch or similar, at least as long as the 
	<quote gcc.info> Deprecated Feature - "implicit typename extension"
	is not removed from g++ code </quote>

>How-To-Repeat:

        The following code generates 
        warnings for the typedef'ed buf_t,
        with 'implicit typename is deprecated'-Warnings disabled:

        g++ -Wno-deprecated s.C 


---------------------
// Code taken from Marcel Loose (loose@astron.nl)
// Posting in gnu.g++.help on 10 Sep 2002 

#include <vector>

template <class T>
class Buffer
{
private:
  typedef std::vector<T> buf_t;

  class Index
  {
  public:
    explicit Index( buf_t::size_type size = 1 );
    operator buf_t::size_type() const;
  private:
    buf_t::size_type myIndex;
    buf_t::size_type mySize;
  };

  buf_t buf;

public:
  explicit Buffer( buf_t::size_type size = 1 );

};

template <class T>
Buffer<T>::Index::Index( buf_t::size_type size ) :
  myIndex( 0 ), mySize( size )
{
}

template <class T>
Buffer<T>::Index::operator Buffer<T>::buf_t::size_type() const
{
  return myIndex;
}

template <class T>
Buffer<T>::Buffer( buf_t::size_type size ) :
  buf(size)
{
}


int main()
{
  Buffer<int> buf(10);
  return 0;
}



>Fix:
>Release-Note:
>Audit-Trail:
>Unformatted: