J3/06-236

Date: 31 July 2006
To: J3
From: Bill Long and John Reid
Subject: Issues 3-6 : image termination
Reference: J3/06-007


Issue 3 (page 16)

The wording was intended to refer to the termination of execution of
all the images. We do not need the concept of 'termination of
execution of the program', but it may be considered to occur after the
asynchronous termination of execution of all the images.

The edits to [16:3-10] and the replacement text in 8.4 (Issues 26-32,
paper 06-245) address this concern.


Issue 4 (page 16)

The editor says 'There is currently no mention of what happens with
signalling exceptions in clause 2, and so no need to mention how it
differs with co-arrays. Therefore the second sentence should be
deleted.'  We agree with the argument and propose to go further:
delete the two paragraphs on termination since the text is repeated in
8.4, and move NOTE 2.4 to 8.4. They are replaced by a simple summary,
optionally along with the text from 04-007 concerning the C exit()
routine that was previously deleted.


Issue 5 (page 17)

After some disucssion we have concluded that an end program statement
should include an implicit sync and cause normal termination of all
the images. The end program statement differs from the STOP statement
in that a program can have only one end program statement.

The intention here is that when a stop that does not follow some form
of synchronization is executed on an image, that image terminates
normally after telling the other images much as if the user had
entered cntl-c at the keyboard. The other images terminate quite soon,
but exactly how soon is processor dependent. Some may terminate
normally. See 06-245 for additional discussion.

The problem lies in the different behaviour when synchronization is
involved.  The intention was that the synchronized images should
collaborate and provide some sort of summary on image 1 of the state
on all images. The editor is suggesting that it would be better to
have a special statement for this.

The subgroup considered this and decided that it was unnecessary since
an immediately preceding synchronization could be defined to have the
same effect.


Issue 6 (page 17)

Note 2.4 is replaced by a new Note in 8.4.


Edits to J3/06-007

Option 1 for [16:3-10] (includes C exit() text):

[16:3-10]. Replace these two paragraphs with the following that
includes the text from 04-007:


"Normal termination of execution of an image occurs if a STOP statement
is executed on that image.  Execution of an <end-program-stmt results
in a synchronization of all images followed by normal termination of
execution of all images. Normal termination of execution of an image
also may occur during execution of a procedure defined by a companion
processor (C International Standard 5.1.2.2.3 and 7.20.4.3). If normal
termination of execution occurs within a Fortran program unit and the
program incorporates procedures defined by a companion processor, the
process of execution termination shall include the effect of executing
the C exit() function (C International Standard 7.20.4.3)."

Option 2 for [16:3-10] (excludes C exit() text):

[16:3-10]. Replace these two paragraphs with one paragraph:

"Normal termination of execution of an image occurs if a STOP statement
is executed on that image.  Execution of an <end-program-stmt results
in a synchronization of all images followed by normal termination of
execution of all images."

Note to Editor: The above edit for [16:3-10] supersedes the edit for
[16:3] in the paper addressing Issues 1 and 2 (paper 06-235).
[end Note to Editor]

[17:1-] Delete NOTE 2.4. A replacement is provided for subclause 8.4 -
see paper 06-245.

[196:16+] Add to the list of image control statements "END PROGRAM
statement;".

[196:21] Replace "control statement, between" with "control statement
or between".

[196:22] Remove ",or after the last image control statement".