[Bug c++/50611] New: Error reporting routines re-entered

["jakub at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50611

             Bug #: 50611
           Summary: Error reporting routines re-entered
    Classification: Unclassified
           Product: gcc
           Version: 4.6.1
            Status: UNCONFIRMED
          Keywords: diagnostic, ice-on-invalid-code
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: jakub@gcc.gnu.org
                CC: jason@gcc.gnu.org


namespace std class multiset;
namespace blue_sky template < class > class smart_ptr;
typedef unsigned ulong;
typedef
blue_sky::smart_ptr < >
  spv_float;
struct wpi_strategy_3d
{
  enum
  {
    D;
    typedef ulong vertex_pos_i
      template <
      class
      strat_t > struct wpi_impl:
      public
    {
      strat_t::D;
      typedef
      std::multiset < >
intersect_path
class
intersect_action
      {
      public:typedef
{
} remove_dups2 ()
{
  typedef int
    dirvec_t[D];
  struct top_surv
  {
  top_surv (dirvec_t &, intersect_path &,)};
  dirvec_t
    dir
  {
top_surv (dir, x_, m_size_)}} intersect_path &
  x_
  vertex_pos_i
  m_size_;
      }
      well_path_ident_d (
  {
  intersect_action A (;
      A.remove_dups2 ()}
      spv_float well_path_ident
      {
      wpi_impl <
      wpi_strategy_3d >::
      well_path_ident_d}
}
}
}

after issuing loads of errors ICEs with
Internal compiler error: Error reporting routines re-entered.
This is delta reduced from https://bugzilla.redhat.com/show_bug.cgi?id=738516
which ICEs both on the 4.6 branch and on the trunk the same way.