[Bug fortran/25829] [F03] Asynchronous IO support

["jvdelisle at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=25829

Jerry DeLisle <jvdelisle at gcc dot gnu.org> changed:

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--- Comment #31 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> ---
(In reply to Nicolas Koenig from comment #30)
> Created attachment 42494 [details]
> Early patch
> 
> Hello everyone,
> 
> attached is a first patch that implements async io for integers. I will
> extend it to work for everything and heavily optimize it before submitting,
> but I would like some feedback on the overall structure.

Lets talk at a little higher level. Some systems provide asynchrounous I/O as a
feature of the OS while others do not.

Are you seeking to implement generically for any system or just those that
support it more directly?

Do we conclude that we must lock all variables in an asynchronous statement or
that they are buffered into the operating system so there is no need to lock
the variables.  As soon as they are "written" to the system, those values have
been copied into the buffer and there is no need to lock. Then the user is
responsible to "WAIT" before doing anything else. ?

I am trying to make sure we all understand how this feature is intended to
work. I think I need to read the standard over. So forgive me if I am off base.