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From: "jvdelisle at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libfortran/93727] Fortran 2018: EX edit descriptor
Date: Sun, 10 Mar 2024 03:37:13 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D93727

--- Comment #5 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> ---
I have been studying this a bit by looking at the 2023 std and functionalit=
y of
printf().
Specifically printf() provides the 'A' descriptor which can be used for flo=
at
(kind=3D4) and double (kind=3D8).  It will accept a long double (80 bit aka
kind=3D10). I am noticing that the results of double and long double are
identical, no extra precision visible. It is very possible I am not doing t=
hat
correctly.

I do not see anything related to quad precision floats.  I am posting this =
as i
think we will have to do some of our own translating byte portions of floats
ourselves. Portability may be an issue. For example IBM 360 128bit precisio=
n or
some other processor may not follow the same internal representations.

Regardless I have preliminary code for the frontend that results in calling
anew fucntion write_ex in transfer.c

I think that kind=3D4 and kind=3D8 will be fine. Any thoughts on kind=3D10 =
or kind=3D16
I would appreciate as I further explore this.=