[Bug libfortran/108056] [12/13 Regression] backward compatibility issue between 11 and 12

["kargl at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108056

--- Comment #6 from kargl at gcc dot gnu.org ---
(In reply to Gilles Gouaillardet from comment #2)
> ubuntu does not ship libgfortran.so from gfortran-11.
> 
> I tried on a RedHat box, and the issue only occurs when
>  - I compile with gfortran-11
>  - *and* I force libgfortran-12

Isn't that forward compatibility?  Backward compatibility
would be something compiled with 12 can use libgfortran from
11.  But, I suspect that is also broken, because ...

> (so if i use the same gfortran and libgfortran versions, there is no issue).
> 
> Here is a stack trace in these conditions:
> 
> #0  0x00002aaaaba2dd70 in _exit () from /lib64/libc.so.6
> #1  0x00002aaaab9a1cab in __run_exit_handlers () from /lib64/libc.so.6
> #2  0x00002aaaab9a1d37 in exit () from /lib64/libc.so.6
> #3  0x00002aaaaacf0976 in _gfortrani_exit_error (status=3) at
> ../../../../src/gcc-12.1.0/libgfortran/runtime/error.c:218
> #4  0x00002aaaaacf12af in _gfortrani_internal_error (cmp=0x0,
> message=0x2aaaaafdf2a5 "Invalid type in descriptor") at
> ../../../../src/gcc-12.1.0/libgfortran/runtime/error.c:534
> #5  0x00002aaaaaf787e2 in _gfortran_gfc_desc_to_cfi_desc
> (d_ptr=0x7fffffffcfa8, s=0x7fffffffcfd0) at
> ../../../../src/gcc-12.1.0/libgfortran/runtime/ISO_Fortran_binding.c:219

a lot of work went into fixing problems with ISO_Fortran_binding.[ch].
It seems that that work either was not merged into 11 or was only 
partially merged.  Either way it appears the ABI of the library has
been broken.

If you're application is using ISO_Fortran_binding.h, then you'll
want to use gfortran 12 or newer.