(j3.2006) Comment 2 from TS Ballot

[Bill Long]

The ISO ballot on the DTS for TS 29133 (Interoperability TS) resulted
in a total of two comments, both technical and from Germany. We
need to create a document containing responses to these comments.

The following starts the discussion of the second comment. Please, 
especially Reinhold, post to the list if you think I have misunderstood 
the intent of the comment.


-------From the Ballot Response for Comment 2-----------------

Technical comment 1 from Germany:

For an entity of [a pointer to] type CFI_cdesc_t that corresponds to a 
non-contiguous Fortran object, accessing parts of the object that would 
not be accessible in Fortran must be explicitly disallowed, because the 
base_addr member is exposed.

Proposed change:

In 8.5, after para 3, add a para 4:
?If a formal parameter of type CFI_cdesc_t corresponds to a dummy 
argument in an interoperable procedure interface, indirection on a 
pointer calculated from its base_addr member is allowed if and only if 
the value of that pointer can be obtained by applying the function 
CFI_address (8.3.5.2) to the object or a subobject of it.?


-------End of Ballot Response for Comment 2-------------------

Discussion:

I had thought that we had something similar to this in the TS in the 
past, but I'm not finding it now.    I'm concerned that  "calculated 
from" in the edit is sufficiently vague that the paragraph is not really 
a solution to the problem.   The real objective is to permit access to 
only elements of the actual argument corresponding to the dummy argument 
in the interoperable procedure interface.    Maybe:

"If a formal parameter that is a pointer to CFI_cdesc_t corresponds to a 
dummy argument in an interoperable interface, a computed pointer may be 
used to access the corresponding actual argument, or a subobject of it, 
  if and only if the value of the computed pointer can be obtained by 
applying the function CFI_address (8.3.5.2) to the formal parameter."

Comments...


Cheers,
Bill


-- 
Bill Long                                           longb at cray.com
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