Examples of Definitions Up: Storage Association Previous: Storage Association


  1. COMMON blocks are either sequential or nonsequential, as determined by either explicit directive or compiler default. A sequential COMMON block has a single common block storage sequence (
  2. An aggregate variable group is a collection of variables whose individual storage sequences are parts of a single storage sequence.

    Variables associated by EQUIVALENCE statements or by a combination of EQUIVALENCE and COMMON statements form an aggregate variable group. The variables of a sequential COMMON block form a single aggregate variable group.

  3. The size of an aggregate variable group is the number of storage units in the group's storage sequence (

  4. If there is a member in an aggregate variable group whose storage sequence is totally associated ( with the storage sequence of the aggregate variable group, that variable is called an aggregate cover.

  5. Variables are either sequential or nonsequential. A variable is sequential if and only if any of the following holds:

    1. it appears in a sequential COMMON block;

    2. it is a member of an aggregate variable group;

    3. it is an assumed-size array;

    4. it is a component of a derived type with the Fortran 90 SEQUENCE attribute; or

    5. it is declared to be sequential in an HPF SEQUENCE directive.

    A sequential variable can be storage associated or sequence associated; nonsequential variables cannot.

  6. A COMMON block contains a sequence of components. Each component is either an aggregate variable group, or a variable that is not a member of any aggregate variable group. Sequential COMMON blocks contain a single component. Nonsequential COMMON blocks may contain several components that may be nonsequential or sequential variables or aggregate variable groups.

  7. A variable is explicitly mapped if it appears in an HPF alignment or distribution directive within the scoping unit in which it is declared; otherwise it is implicitly mapped.

Examples of Definitions Up: Storage Association Previous: Storage Association
Thu Jul 21 17:05:43 CDT 1994