[Fortran] Improved dependency analysis of pointer variables

[Paul Thomas]

Roger,

>Ok for mainline?
>  
>
OK, subject to one comment/correction.

Paul

>
>! 	  /* Symbols can only alias if they have the same type.  */
>! 	  if (ts1->type != BT_UNKNOWN
>! 	      && ts2->type != BT_UNKNOWN
>! 	      && ts1->type != BT_DERIVED
>! 	      && ts2->type != BT_DERIVED)
>! 	    {
>! 	      if (ts1->type != ts2->type
>! 		  || ts1->kind != ts2->kind)
>! 		return 0;
>! 	    }
>  
>
This is too restrictive of derived types, isn't it? You could use 
interface.c (gfc_compare_derived_types, gfc_compare_derived_types) to 
determine if the types are the same; that way, derived types are tested too.

Paul