anchor.diff:    subroutine BRINGU(Zpiv,Iperm,Invp,Parent,Izz,Neqns,Irr)
       implicit none
       !------
  -    integer, intent(in):: Izz
  -    integer, intent(in):: Neqns
  -    integer, intent(in):: Zpiv(*)
  -    integer, intent(in):: Parent(*)
  -    integer, intent(out):: Irr
  -    integer, intent(inout):: Iperm(*)
  -    integer, intent(inout):: Invp(*)
  -    !------
  -    integer:: i
  -    integer:: ib
  -    integer:: ib0
  -    integer:: ibp
  -    integer:: idbg
  -    integer:: izzp
  +    integer(kind=kint), intent(in):: Izz
  +    integer(kind=kint), intent(in):: Neqns
  +    integer(kind=kint), intent(in):: Zpiv(*)
  +    integer(kind=kint), intent(in):: Parent(*)
  +    integer(kind=kint), intent(out):: Irr
  +    integer(kind=kint), intent(inout):: Iperm(*)
  +    integer(kind=kint), intent(inout):: Invp(*)
  +    !------
  +    integer(kind=kint):: i
  +    integer(kind=kint):: ib
  +    integer(kind=kint):: ib0
  +    integer(kind=kint):: ibp
  +    integer(kind=kint):: idbg
  +    integer(kind=kint):: izzp
   
       idbg = 0
       Irr = 0
  
positive.code:   subroutine INV6(Dsln,Ir)
      implicit none
      !------
      integer, intent(out):: Ir
      real(kind=8), intent(inout):: Dsln(21)
      !------
      real(kind=8):: t(5)
  
      Ir = 0
      Dsln(1) = 1.0D0/Dsln(1)
  
negative.code:   subroutine NUFCT3(Xlnzr,Colno,Dsln,Zln,Diag,Indx,Temp,Neqns,Parent,Nch,Nstop,Ir)
      implicit none
      !------
      integer(kind=kint), intent(in):: Neqns
      integer(kind=kint), intent(in):: Nstop
      integer(kind=kint), intent(in):: Xlnzr(*)
      integer(kind=kint), intent(in):: Colno(*)
      integer(kind=kint), intent(in):: Parent(*)
      integer(kind=kint), intent(out):: Ir
      integer(kind=kint), intent(out):: Indx(*)
      integer(kind=kint), intent(inout):: Nch(*)
      real(kind=kreal), intent(inout):: Zln(9,*)
      real(kind=kreal), intent(inout):: Diag(6,*)
      real(kind=kreal), intent(out):: Temp(*)
      real(kind=kreal), intent(inout):: Dsln(9,*)
      !------
      integer(kind=kint):: ic
      integer(kind=kint):: l
      real(kind=kreal):: t1
      real(kind=kreal):: t2
      real(kind=kreal):: t3
      real(kind=kreal):: t4
      real(kind=kreal):: t5
      real(kind=kreal):: tt
  
      !
      ! phase I
  