[Bug fortran/84594] Warning: Use of the NUMERIC_STORAGE_SIZE named constant from intrinsic module ISO_FORTRAN_ENV at (1) is incompatible with option -fdefault-integer-8

["sgk at troutmask dot apl.washington.edu" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84594

--- Comment #3 from Steve Kargl <sgk at troutmask dot apl.washington.edu> ---
On Wed, Feb 28, 2018 at 12:01:38PM +0000, dominiq at lps dot ens.fr wrote:
> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84594
> 
> --- Comment #2 from Dominique d'Humieres <dominiq at lps dot ens.fr> ---
> > This is expected.
> 
> Indeed! I have found it in module.c.
> 
> > This PR should be closed as INVALID.
> 
> (1) AFAICT this not documented. Is NUMERIC_STORAGE_SIZE the only parameter in
> ISO_FORTRAN_ENV triggering a warning?
> 

Don't know.  But, it is obviously a correct warning
as -fdefault-integer-8 applies to only the default
integer kind while NUMERIC_STORAGE_SIZE applies to
all numeric types.

> (2) The warning is not emitted with -fdefault-real-10 nor with
> -fdefault-real-16. I guess this was overlooked when these options were added.
> 
> (3) The options -finteger-4-integer-8 and -freal-*-real-* don't trigger the
> warning. Is it because they change all the occurrences of INT or REAL, while
> -fdefault-* only change the implicit ones?

AFAIK, Yes.  INTEGER(4) is known to the compiler with -finteger-4-integer-8,
the user simply cannot use it as internally gfortran map everything
to INTEGER(8) as-if the user actually ported the code.   In other words,
storage association isn't broken by these options.

> (4) I stumbled on this warning while running the test suite with
> -fdefault-integer-8 and I'ls like to decrease the noise by using one of the
> following:

The testsuite is designed to test bug fixes and correctness of
new added features (e.g., PDT).  It isn't designed to run with
the-option-of-day.

> (a) add an ONLY clause;

Breaks the possibility of detecting errors when fixing a real bug.

> (b) add a dg-prune-output;

Breaks the possibility of detecting errors when fixing a real bug.


These, of course, are just my opinions.  Feel free to 
ignore them.  Personally, I would prefer that -fdefault-*
option be removed, but I cannot get support for that.