bad interaction between allocatable arrays and bind(C) subroutine with dimension(..) parameter

[Paul Richard Thomas]

Hi Gilles,

Something has gone wrong with the bounds. Before the call, lbound(buf)
is 1 and after it is 0.

I'll take a look.

Cheers

Paul

On Tue, 1 Oct 2019 at 05:15, Gilles Gouaillardet <gilles@rist.or.jp> wrote:
>
> Hi Paul,
>
>
> did you have any chance to investigate the issue I previously reported?
>
>
> I would like to emphasize the test program I attached (that involves the
> LOC() intrinsic) is a toy program
>
> whose sole purpose is to evidence the issue.
>
>
> I will be happy to provide a more close to real-life program if needed.
>
> FWIW, I initially found this issue when testing MPI Fortran 2008
> bindings with the TS interface
>
> (long story short, the allocatable array becomes invalid after it is
> passed as a parameter
>
> to a MPI subroutine).
>
>
> Cheers,
>
>
> Gilles
>
> On 8/20/2019 4:19 PM, Gilles Gouaillardet wrote:
> > Folks,
> >
> >
> > The attached program evidences an issue when an allocatable array is
> > passed to
> >
> > a bind(C) subroutine that takes a type(*), dimension(..) argument.
> >
> >
> > The expected output is :
> >
> > OK: allocatable
> >
> > OK: static
> >
> > but with gcc 9.1.0, 9.2.0 and the latest master, the output is :
> >
> > KO: allocatable
> >
> > OK: static
> >
> >
> > Note the test is successful if the argument is declared as type(*),
> > dimension(*).
> >
> >
> > Incidentally, I also noted that if the test program is compiled with
> > -g -O0 and ran under gdb (I tried 7.6.1-110.el7 provided by CentOS 7),
> >
> > the type of 'buf' as reported by the gdb whatis command changes after
> > the call to the bind(C) subroutine
> >
> > 22        CALL dummy (buf)
> > (gdb) whatis buf
> > type = integer(kind=4) (1)
> > (gdb) n
> > 23        after = LOC(buf(1))
> > (gdb) whatis buf
> > type = integer(kind=4) (0:0)
> >
> >
> > FWIW, the test is successful with Intel compilers (I tried 2018.3 and
> > 2019.3)
> >
> >
> > Could you please investigate this issue ?
> >
> >
> > Cheers,
> >
> >
> > Gilles
> >



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