anchor.diff:       &   dx,iwinkx,winkx,numslp,numsn,nwinkx,                           ! slip
        &   tfault,numfn,                                                  ! fault
        &   s,stemp,                                                       ! stiff
  -     &   state,dstate,dmat,ien,lm,lmx,lmf,infiel,iddmat,nstatesz,       ! elemnt
  -     &   ndmatsz,numelt,nconsz,                                         ! elemnt
  +     &   state,dstate,state0,dmat,ien,lm,lmx,lmf,infiel,iddmat,nstatesz,! elemnt
  +     &   nstatesz0,ndmatsz,numelt,nconsz,nprestrflag,ipstrs,ipauto,     ! elemnt
  +     &   nstate0,                                                       ! elemnt
        &   prop,mhist,infmat,infmatmod,numat,npropsz,tminmax,             ! materl
        &   gauss,sh,shj,infetype,                                         ! eltype
        &   histry,rtimdat,ntimdat,rgiter,nhist,lastep,                    ! timdat
  
positive.code: c
        subroutine autoprestr(
       & alnz,pcg,zcg,dprev,ja,                                           ! sparse
       & bextern,btraction,bgravity,bconcforce,bprestress,bintern,bresid, ! force
       & bwork,dispvec,nforce,grav,                                       ! force
       & x,d,deld,dcur,id,iwink,wink,nsysdat,                             ! global
       & ibond,bond,                                                      ! bc
       & dx,deldx,dxcur,diforc,idx,iwinkx,winkx,idslp,ipslp,idhist,       ! slip
       & fault,nfault,dfault,tfault,                                      ! fault
       & s,stemp,                                                         ! stiff
       & state,dstate,dmat,ien,lm,lmx,lmf,infiel,iddmat,npar,             ! elemnt
       & ielno,iside,ihistry,pres,pdir,                                   ! tractn
       & prop,mhist,infmat,infmatmod,ismatmod,                            ! materl
       & gauss,sh,shj,infetype,                                           ! eltype
  
negative.code:       call fill(dx,zero,ndof*numnp)
        call fill(dxcur,zero,ndof*numnp)
        call fill(state,zero,nstr*nstatesz)
        call fill(state0,zero,nstate0*nstatesz0)
        call fill(dmat,zero,nddmat*ndmatsz)
        call fill(dstate,zero,nstr*nstatesz)
        if(numfn.ne.izero) call fill(tfault,zero,numfn*ndof)
  