Hi Steve,
On 1/22/20 4:54 PM, Steve Kargl wrote:
Supposedly, one can use attr.is_c_interop and attr.is_iso_c to
determine if something is interoperable (if it is consistently set)
and if it is from the ISO C Binding module.
I think this is fixable on two sides:
* For the used tree type, one just has to check kind value (the integer)
plus whether the dummy's procedure is BIND(C). Here the problem is that
we do not always have this information available (i.e. it needs to be
passed on). Not difficult, but one needs to find all spots and think of
how to pass the information.
* For the diagnostic, we can check whether the dummy argument is in
bind(C) and do some additional diagnostic in this case (e.g. always warn
for kind=4 with BIND(C) – or reject it unconditionally or with -std=...
or …).
* The other issue related to kind=4: Fortran permits to pass a too long
string as actual argument; but this is only permitted in the standard
for kind=1 and kind=c_char strings. In gfortran, this also works fine
with kind=4 – but one might still want to warn (with some -Wall or
-std=f... or ...). Likewise, the trimming happening in this case might
indicate a bug in the program: "Hello World" as actual to
character(len=10) is most likely a bug, even if this is valid Fortran.
Cheers,
Tobias
