Explicit interface for structures and allocatable arrays

[OP1]

When a subroutine has a dummy array with the ALLOCATABLE attribute, an explicit interface is required.

If a subroutine has a dummy variable which is a user defined structure (TYPE(my_structure) for instance), and if one of this structure's component is an allocatable array, then no explicit interface is required.

Why is there a difference?

[BTW: these two features (allocatable dummy argument and allocatable structure component) are an extremely welcome addition to the Fortran language!!]

Olivier

[Steven_L_Intel1 · Accepted solution]

An allocatable array argument is always deferred-shape which requires an explicit interface so that the descriptor can be passed. For a derived type with allocatable components, it could be a fixed-shape array which does not require an interface.

[OP1]

Quoting - Steve Lionel (Intel)

An allocatable array argument is always deferred-shape which requires an explicit interface so that the descriptor can be passed. For a derived type with allocatable components, it could be a fixed-shape array which does not require an interface.

Thanks Steve!