[Bug debug/67664] [6 Regression] Duplicate AT_const_value attributes in some c++ cases.

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67664

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
Reduced testcase:

struct T
{
  static const int a = 0;
};

int main()
{
  T t;
  return t.a;
}