anchor.diff:    integer, parameter :: XC_D10300 =  82
     integer, parameter :: XC_D00400 = 112
   
  -! tau mgga
  +! seven-variable derivatives up to order 4
   ! so far only linear response
  -! list under construction ...
     integer, parameter :: XC_D0000000 =  1
     integer, parameter :: XC_D1000000 =  2
     integer, parameter :: XC_D0010000 =  4
  
positive.code:   integer, parameter :: XC_D13 = 14
    integer, parameter :: XC_D04 = 15
  
  ! gga up to order 4
  ! only derivatives that are nonzero at closed-shell reference
  ! with XC_VARS_NS are here
    integer, parameter :: XC_D00000 =   1
  
negative.code: module xcfun
    use xcfun_autogen
    implicit none
  
  ! these parameters should mirror those in xcfun.h
    integer, parameter ::  XC_VARS_A  = 0
    integer, parameter ::  XC_VARS_N  = 1
    integer, parameter ::  XC_VARS_AB = 2
  