[Bug c++/31881] New: inherited members invisible within nested class within templated class

[Bug c++/31881] New: inherited members invisible within nested class within templated class

[ghood at psc dot edu]

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Here is the code (nest.cc) that exhibits the error:

template<class X>
class A
{
public:
  class B
  {
  public:
    int i;
  };

  class C: public B
  {
  public:
    void f()
    {
      this->i;   // OK

      i;         // results in "error: ‘i’ was not declared in this scope"
                 //   even though i should be inherited from B
    }
  };
};

This code generate an error when compiled with "g++ -v -save-temps -c nest.cc"
on powerpc-linux-gnu using gcc 4.1.2, on i386-redhat-linux using gcc 4.1.0,
and on x86_64-redhat-linux using gcc 3.4.5.  This is somehow related to the
classes being templated because removing the template<class X> line will
eliminate the error.

It compiles without problem on i386-redhat-linux using gcc 3.2.2, on
x86_64-redhat-linux using PGI's pgCC 6.1.6, and on x86_64-redhat-linux using
Intel's icc 9.1.


-- 
           Summary: inherited members invisible within nested class within
                    templated class
           Product: gcc
           Version: 4.1.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: ghood at psc dot edu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31881

[Bug c++/31881] inherited members invisible within nested class within templated class

[ghood at psc dot edu]

------- Comment #1 from ghood at psc dot edu  2007-05-09 17:22 -------
Created an attachment (id=13534)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=13534&action=view)
nest.ii


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31881

[Bug c++/31881] inherited members invisible within nested class within templated class

[pinskia at gcc dot gnu dot org]

------- Comment #2 from pinskia at gcc dot gnu dot org  2007-05-09 17:23 -------
I don't think this is a bug. class B is dependent so the inherited elements are
not seen.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31881

[Bug c++/31881] inherited members invisible within nested class within templated class

[ghood at psc dot edu]

------- Comment #3 from ghood at psc dot edu  2007-05-09 19:04 -------
OK, I now understand the issue here.  The fact that B and C were not
explicitly templatized, and the other compilers accepted it, led me
to think that it was valid code.  In case anyone else is interested,
there's an explanation at:
http://womble.decadentplace.org.uk/c++/template-faq.html#base-lookup

Thanks.


-- 

ghood at psc dot edu changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |INVALID


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31881