Topic: Access violation in Support

I have been involved in trying to get some Fortran 90 running on the PC that was previously run on Unix systems using other compilers. Compilation was done with 'Global save on'

The messages are:

Access violation The instructions at address 036d410a attempted to read from location 20727774

036d4070 __CONCAT (+009a) 0043ff00 LP_NETWORK!NEW_NODE_INDS [+105] 00404609 EVALUATOR!PREPARE_NETWORK_CMAT [+0558]

The routine with the problem is

SUBROUTINE new_node_inds ( cmat, nodes, error_status )

! Escargot Stage 1 Functional Specification Issue 2 Draft 6 ! '4.2 Disconnection Generators' ... first equation (8)

! Allocates two independent variables for the node: ! Create a disconnection power variable for the demand not met at the node. ! This variable greatly improves the likelyhood of a feasible solution. ! Put it into the initial basis except for the reference node. ! Give it a large arbitrary limit. ! Create a voltage phase angle variable. ! Omit it from the initial basis except for the reference node. ! Give it a large arbitrary limit.

TYPE(cons_matrix), INTENT(INOUT) :: cmat ! Constraint matrix TYPE(node_data), INTENT(INOUT), TARGET :: nodes(:) ! Node data INTEGER, INTENT(OUT) :: error_status ! Error status code

! Global data ! costs (IN)

! Local data CHARACTER(*), PARAMETER :: proc_id = mod_id//'nni:' ! Subroutine identifier TYPE(obj_ref), DIMENSION(1:2) :: node_obj ! Object reference for ! node variable INTEGER :: inode ! Node number

! ------------------- Executable code ------------------- !

error_status = success

! All nodes DO inode = 1, numnod node_obj = (/ obj_ref('node',nodes(inode)%inp%name, inode) , & obj_ref('pwr','',0 ) /)

! The disconnection generator makes up any supply that cannot be met nodes(inode)%work%inds%pwr = new_ind (cmat, & & 'Disconnection power at node '//nodes(inode)%inp%name, & & cost=costs%disc, inicst=zero, low=zero, high=lims%medpwr, & & objs=node_obj)
IF ( nodes(inode)%work%inds%pwr .LE. 0 ) THEN error_status = sev_error CALL message ( proc_id//'dvn', sev_error, & 'Error allocating disconnection variable for node [NAME]' , & nodes(inode)%inp%name ) RETURN END IF

! The nodal phase angle is an independent variable. node_obj(2) = obj_ref('ang','',0) IF ( nodes(inode)%work%section == inode ) THEN

  ! For a reference node, the nodal angle must be basic.
     nodes(inode)%work%inds%ang = new_ind (cmat,        &amp;
      &amp; 'Phase angle at Node '//nodes(inode)%inp%name,  &amp;
      &amp; cost=zero, inicst=zero, low=zero, high=zero,    &amp;
      &amp; objs=node_obj)  
  ELSE IF ( nodes(inode)%work%section > 0 ) THEN

  ! For a non-reference node, the nodal angle must be non-basic.
  ! The corresponding power balance dependent variable must be
  ! made basic to ensure the correct number of basic variables.
     nodes(inode)%work%inds%ang = new_ind (cmat,        &amp;
      &amp; 'Phase angle at Node '//nodes(inode)%inp%name,  &amp;
      &amp; cost=zero, inicst=zero, low=-lims%bigang,       &amp;
      &amp; high=lims%bigang, objs=node_obj)
  ! If ( nodes(inode)%work%section < 0 ), inode is not in use
  END IF
  IF ( nodes(inode)%work%inds%ang <= 0 ) THEN
     error_status = sev_error
     CALL message ( proc_id//'dph', sev_error,                  &amp;
        'Error allocating phase angle variable for node [NAME]' ,   &amp;
            nodes(inode)%inp%name )
     RETURN
  END IF

END DO

END SUBROUTINE new_node_inds

The problem appears to relate to the concatenation in the call to new_ind call as I get a different access violation if I modify the call to:

  nodes(inode)%work%inds%pwr = new_ind (cmat,                  &amp;
   &amp; 'Disconnection power at node '//nodes(inode)%inp%name,    &amp;
   &amp; cost=costs%disc, inicst=zero, low=zero, high=lims%medpwr, &amp;
   &amp; objs=node_obj)