5.8.1  Implicit Data-Mapping Attribute Rules

When specified, explicit data-environment attribute clauses on target directives determine the attributes for variables referenced in a target construct. Otherwise, the first matching rule from the following list determines the implicit data-mapping (or data-sharing) attribute for variables referenced in a target construct that do not have a predetermined data-sharing attribute according to Section 5.1.1. References to structure elements or array elements are treated as references to the structure or array, respectively, for the purposes of determining implicit data-mapping or data-sharing attributes of variables in a target construct.

• If a variable appears in an enter or link clause on a declare target directive that does not have a device_type clause with the nohost device-type-description then it is treated as if it had appeared in a map clause with a map-type of tofrom.
• If a variable is the base variable of a list item in a reduction, lastprivate or linear clause on a combined target construct then the list item is treated as if it had appeared in a map clause with a map-type of tofrom if Section 17.2 specifies this behavior.
• If a variable is the base variable of a list item in an in_reduction clause on a target construct then it is treated as if the list item had appeared in a map clause with a map-type of tofrom and a map-type-modifier of always.

• If a defaultmap clause is present for the category of the variable and specifies an implicit behavior other than default, the data-mapping or data-sharing attribute is determined by that clause.

  ∙ If the target construct is within a class non-static member function, and a variable is an accessible data member of the object for which the non-static data member function is invoked, the variable is treated as if the this[:1] expression had appeared in a map clause with a map-type of tofrom. Additionally, if the variable is of type pointer or reference to pointer, it is also treated as if it had appeared in a map clause as a zero-length array section. ∙ If the this keyword is referenced inside a target construct within a class non-static member function, it is treated as if the this[:1] expression had appeared in a map clause with a map-type of tofrom.
  ∙ A variable that is of type pointer, but is neither a pointer to function nor (for C++) a pointer to a member function, is treated as if it is the base pointer of a zero-length array section that had appeared as a list item in a map clause.
  ∙ A variable that is of type reference to pointer, but is neither a reference to point to function nor a reference to a pointer to a member function is treated as if it had appeared in a map clause as a zero-length array section.

• If a variable is not a scalar then it is treated as if it had appeared in a map clause with a map-type of tofrom.

  ∙ If a scalar variable has the TARGET, ALLOCATABLE or POINTER attribute then it is treated as if it had appeared in a map clause with a map-type of tofrom.
• If the above rules do not apply then a scalar variable is not mapped but instead has an implicit data-sharing attribute of firstprivate (see Section 5.1.1).