[Bug c++/22427] New: member function template of partial specialized class template

["zhaojiangbin at yahoo dot com" <gcc-bugzilla at gcc dot gnu dot org>]

Case 1:

The following code is rejected by GCC 4.0.1 and GCC 4.0.0:

=== begin ===

template < class C, class T >
struct A
{
  template < class G >
  void f( G& g )
  {
    g.f1();
  }
};

// (a)

template < class T > // (c)
template < class G >
void
A< char, T >::f( G& g ) // (b)
{
  g.f2();
}

=== end ===

The compiler says "error: no member function 'f' declared in 'A<char, T>'" and
"error: invalid function declaration" at point (b).

Case 2:

But if a partial specialization of class template A, as below, is inserted at
point (a) in case 1, the compilers accept the code:

=== begin ===

template < class T >
struct A< char, T >
{
  template < typename G >
  void f( G& g );
};

=== end ===

Case 3:

The compiler also accepts the code if the function definition at point (c) in
case 1 is defined as below, even without the partial specialization of class
template A in case 2:

=== begin ===

template <>
template < class G >
void
A< char, int >::f( G& g )
{
  g.g2();
}

=== end ===


Case 4:

If the member function f() is not a template, as below, the error messages are
"error: invalid use of undefined type 'A<char, T>'" at point (d), "error:
declaration of struct 'A<char, T>'" at point (e), and "error: template
definition of non-template 'void A<char, T>::f()'" at point (d):

=== begin ===

template < class C, class T >
struct A
{ // (d)
  void f() {}
};

template < class T >
void
A< char, T >::f() // (e)
{}

=== end ===


The compilers tested are Debian 4.0.0-7:

=== begin ===

Using built-in specs.
Target: i486-linux
Configured with: ../src/configure -v
--enable-languages=c,c++,java,f95,objc,ada,treelang --prefix=/usr
--enable-shared --with-system-zlib --libexecdir=/usr/lib --enable-nls
--without-included-gettext --enable-threads=posix --program-suffix=-4.0
--enable-__cxa_atexit --enable-libstdcxx-allocator=mt --enable-clocale=gnu
--enable-libstdcxx-debug --enable-java-gc=boehm --enable-java-awt=gtk
--enable-mpfr --disable-werror --enable-checking=release i486-linux
Thread model: posix
gcc version 4.0.1 20050509 (prerelease) (Debian 4.0.0-7)

=== end ===

and Debian 4.0.1-1:

=== begin ===

Using built-in specs.
Target: i486-linux-gnu
Configured with: ../src/configure -v
--enable-languages=c,c++,java,f95,objc,ada,treelang --prefix=/usr
--enable-shared --with-system-zlib --libexecdir=/usr/lib --enable-nls
--without-included-gettext --enable-threads=posix --program-suffix=-4.0
--enable-__cxa_atexit --enable-libstdcxx-allocator=mt --enable-clocale=gnu
--enable-libstdcxx-debug --enable-java-gc=boehm --enable-java-awt=gtk
--with-java-home=/usr/lib/jvm/java-1.4.2-gcj-4.0-1.4.2.0/jre --enable-mpfr
--disable-werror --enable-checking=release i486-linux-gnu
Thread model: posix
gcc version 4.0.1 (Debian 4.0.1-1)

=== end ===

-- 
           Summary: member function template of partial specialized class
                    template
           Product: gcc
           Version: 4.0.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: zhaojiangbin at yahoo dot com
                CC: gcc-bugs at gcc dot gnu dot org
  GCC host triplet: i486-linux-gnu
GCC target triplet: i486-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=22427