J3/03-120r1

To: J3
From: Toon Moene
Subject: Edits for UK comment MTC11 (Separate C data & procedure pointers)
Date: 2-apr-2003

Comment MTC11 of the UK vote was:

    Have separate types for C data and procedure pointers.

    Function C_LOC operates on either pointers or functions.  In C,
    pointers and functions are separate and it is confusing to mix them
    in Fortran.  There should be a separate type C_FUNPTR for C
    function pointers.

    Edits related to the specification of the C_LOC function are moved
    to paper 03-105r2. Edits to add C_FUNPTR and C_NULL_PTR elsewhere
    in section 15 are in this paper.

Here are the edits for this:

381:14. Change "C_PTR and C_NULL_PTR" to "C_PTR, C_FUNPTR, C_NULL_PTR and
   C_NULL_FUNPTR".

382:9 Replace the line by "The entities C_PTR and C_FUNPTR are
   described in 15.2.2.".

382:11. Add to end of paragraph
  "The entity C_NULL_FUNPTR shall be a named constant of type C_FUNPTR.
   The value of C_FUNPTR shall be that of a null pointer to a function in C."
{We could come right out and say something like "(int (*)(void))0", but
that seems unnecessary.}

383:16. Change "C_PTR" to "C_PTR or C_FUNPTR".

383:17. Change "type C_PTR" to "the same type as C_PTR_1".

386:2-3. Replace by

    C_PTR and C_FUNPTR shall be derived types with private components.
    C_PTR is interoperable with any C object pointer type. C_FUNPTR is
    interoperable with any C function pointer type.

386:3+2. Change "required to have the same representation method for
    all C pointer types" to "required to have the same representation
    method for all C object pointer types and the same representation
    method for all C function pointer types".

386:3+10. Change "C_PTR" to "C_FUNPTR or C_PTR".

387:5+4. Change "C_PTR" to "C_FUNPTR or C_PTR".