[Bug c++/63809] New: Missing warning on extra template

[glisse at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63809

            Bug ID: 63809
           Summary: Missing warning on extra template
           Product: gcc
           Version: 5.0
            Status: UNCONFIRMED
          Keywords: diagnostic
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: glisse at gcc dot gnu.org

wide-int.h contains code like:

  template <>
  template <typename T1, typename T2>
  struct binary_traits <T1, T2, FLEXIBLE_PRECISION, FLEXIBLE_PRECISION>
  {
    typedef widest_int result_type;
  };

g++ fails to warn about the extra parameter list. clang does warn, see PR63750.