To: J3                                                     J3/21-108r1
From: Bill Long & Malcolm Cohen
Subject: Definition status of allocated pointer object
Date: 2021-February-20
Reference: 21-007


Discussion:
-----------

In 19.5.2.8 Relationship between association status and definition
status, we have the sentence in 21-007:

"When a pointer is allocated, it becomes associated but undefined."

But if the ALLOCATE statement that allocates the pointer has a SOURCE=
specifier, the sentence in 19.5.2.8 seems incorrect.

Similarly, there are features like zero-sized arrays, zero-sized
strings, and component initialization, which all falsify that sentence.

In fact, the entirety of 19.5.2.8 is redundant or wrong.

The first sentence follows trivially from the requirements specified in
8.5.14 POINTER attribute (which has much more stringent requirements!).
The second sentence is untrue - INTENT(IN) pointers cannot be nullified,
pointer-assigned or allocated.
The third sentence is redundant with the NULLIFY statement description.
The fourth sentence (the one we're looking at) is, where it is not wrong,
redundant with ALLOCATE and 19.5.2.1.
The final sentence is nonsense for procedure pointers and follows trivially
from 19.5.2.1 for data pointers.

Finally, the subclause claims to be about the relationship between
association status and definition status, but just lists a bunch of random
stuff. The relationship between association status and definition status
is specified completely in 19.5.2.1, which says
    "If a pointer is associated with a target, the definition status of the
     pointer is either defined or undefined, depending on the definition
     status of the target."
Admittedly this itself could be simplified to
    "The definition status of an associated data pointer is that of its
     target."
And that would be a good thing, to stop talking about the definition status
of procedures!

Edits to 21-007
----------------

[524:7-9] 19.5.2.1 General (in 19.5.2 Pointer association), p1,
Change
    "If a pointer is associated with a target, the definition status of the
     pointer is either defined or undefined, depending on the definition
     status of the target."
to
    "The definition status of an associated data pointer is that of its
     target."
{Simplify sentence and don't say that procedure pointers have a definition
 status.}

[527:1-5] 19.5.2.8 Relationship between association status and definition
          status,
    Delete entire subclause.
{Redundant, wrong, redundant, and unhelpful.}

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