[Bug c++/84820] New: [6/7/8 Regression] Bogus pointer-to-member accepted within template

[reichelt at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84820

            Bug ID: 84820
           Summary: [6/7/8 Regression]  Bogus pointer-to-member accepted
                    within template
           Product: gcc
           Version: 8.0
            Status: UNCONFIRMED
          Keywords: accepts-invalid
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: reichelt at gcc dot gnu.org
  Target Milestone: ---

The following invalid code snippet is wrongly accepted since GCC 4.9.0:

================================
struct A {};

template<int> struct B : A
{
  B()
  {
    A(&A::foo);
  }
};

B<0> b;
================================

Before, the code was correctly rejected:

bug.cc: In constructor 'B<<anonymous> >::B()':
bug.cc:7:14: error: invalid use of qualified-name 'A::foo'
     A(&A::foo);
              ^