(j3.2006) Intrinsic assignment of derived types

[Steve Lionel]

Consider:

    type :: t
    end type

    type, extends(t) :: e
    end type

    type(t) :: foo
    class(t), allocatable :: bar

    allocate( e :: bar )

    foo = bar

end

Is the assignment of bar to foo valid, and if so, what does it do? 
Referencing 18-007, 10.2.1.2 requires that the type of the expr be "the 
same derived type as the variable". Here they are of the same declared 
type, but not the same dynamic type.

Then in 10.2.1.3p13,? it says, "An intrinsic assignment where the 
variable is of derived type is performed as if each component of the 
variable
were assigned from the corresponding component of expr..." One could 
interpret this as copying only the components of bar that are in foo. 
One compiler I have access to allows this, another does not, complaining 
that the types don't match.

What exactly does "same derived type" mean here? Would it be 
correct/useful to change the words in table 10.8 to say "same dynamic type"?

Steve


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