[Bug fortran/102145] TKR mismatches with -pedantic: -fallow-argument-mismatch does not degrade errors to warnings

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102145

--- Comment #3 from Steve Kargl <sgk at troutmask dot apl.washington.edu> ---
On Wed, Sep 08, 2021 at 02:14:26PM +0000, ripero84 at gmail dot com wrote:
> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102145
> 
> --- Comment #2 from ripero84 at gmail dot com ---
> 1) The gfortran manual has its own entries for -pedantic and -pedantic-errors:
> 

Seems I owe you an apology.  I failed to check the gfortran
manual as I assumed these options where inherited from gcc
general option pool, and thus, documented in the gcc manual.

(option descriptions removed)

> 2) This answers part of my issue: the behaviour is indeed
>    documented, just in a way that has proved confusing to me.

Well, there are lots of things that gfortran does that I
find confusing, and I've contributed to some of it. ;)

>  It think that a more accurate description
> would start with: 
> 
> -pedantic: Issue warnings for some uses of extensions to Fortran, raise
> otherwise warnings to errors for others.  Not all extensions will raise
> warnings or errors.
> 
> which sounds bad.

Yes, it sounds bad, but at least reflects reality.  -pedantic
is not really pedantic.

> 3) If this is the intended behaviour I can propose some tweaks
> to the documentation, but as I said first I would like to have
> a confirmation (ideally by the person who set up the interaction
> between -pedantic and -fallow-argument-mismatch) that this is
> really intended behaviour, not accidental.

You would need to ping Thomas about the intended behavior.

> 
> 4) Apologies for not going into the C discussion, my C is limited,
>

No apology needed given gfortran's manual documents (badly?)
these options.  Given the lack of volunteers to maintain 
gfortran at the moment, the best path forward may be an
attempt to clarify the option descriptions.

After years of contributing to gfortran, I have come to the
conclusion that all extensions should require options to
permit them.  -std=gnu would activate the options; while, 
any other -std=... would de-active all of the extensions
and issue errors.  But, that ship has sailed.