Error: amd_fill_namelist_block is not available in FTN95/64

Given the code below, which is a pared-down skeleton of something else that does useful calculations, FTN95 8.10 fails with the error shown in the thread title when the options /64 /opt are specified.

      SUBROUTINE ORDDRV
      IMPLICIT NONE
      INTEGER :: ITAPE, IU1EL
      INTEGER :: NFTTAIL = 96, IPFLG = 0, I1ONLY = 0

      NAMELIST /INPUTO/ IPFLG, IU1EL, I1ONLY, NFTTAIL
!
      IU1EL=2
      ITAPE=IU1EL
      CALL OPENU(ITAPE)
      RETURN
!
      END SUBROUTINE ORDDRV

The error goes away if /opt is not used or /64 is not used or slight changes are made to the code (such as initializing IU1EL in the declaration rather than with a separate statement).

Thank you for the feedback. I have made a note of this.

This fragment of code compiles with /64 /opt at v8.40. It appears to have been fixed in some other context.