(j3.2006) a question on same_type_as and type parameters

[Jim Xia]

Just to clarify this issue.  Consider the following program

    class(*), allocatable :: a, b
 
    allocate (real :: a)
    allocate (double precision :: b)
 
    print *, same_type_as (a, b)
    end

Should the PRINT statement print true or false?  Based on the standard, it 
seems that only type matters in deterring the value of the intrinsic, so 
it appears the program should print true.  However this may not provide 
enough information for the user since there is no way to query a or b's 
type parameter values.  So it's still unclear to the user, for example, if 
the two entities are of the same size so it's safe to do an internal 
memory transfer from a to b.  So the question is: do we really intend to 
have the SAME_TYPE_AS only checks for the types of two variables and 
ignore their type parameter values?

The same question also applies to parameterized derived types as can be 
illustrated by the following example


    type t (k)
        integer, kind :: k

        real :: x(k)
    end type
 
    type (t(5)) a
    type (t(10)) b
 
    print *, same_type_as (a, b)
    end


Jim Xia

RL Fortran Compiler Test
IBM Toronto Lab at 8200 Warden Ave, Markham, On, L6G 1C7
Phone (905) 413-3444  Tie-line 313-3444
email: jimxia at ca.ibm.com
D2/YF7/8200 /MKM
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