[Bug fortran/99798] ICE when compiling a variant of pr87907

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99798

--- Comment #4 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Mikael Morin <mikael@gcc.gnu.org>:

https://gcc.gnu.org/g:38d1761c0c94b77a081ccc180d6e039f7a670468

commit r15-698-g38d1761c0c94b77a081ccc180d6e039f7a670468
Author: Mikael Morin <mikael@gcc.gnu.org>
Date:   Sun May 12 15:16:23 2024 +0200

    fortran: Assume there is no cyclic reference with submodule symbols
[PR99798]

    This prevents a premature release of memory with procedure symbols from
    submodules, causing random compiler crashes.

    The problem is a fragile detection of cyclic references, which can match
    with procedures host-associated from a module in submodules, in cases where
it
    shouldn't.  The formal namespace is released, and with it the dummy
arguments
    symbols of the procedure.  But there is no cyclic reference, so the
procedure
    symbol itself is not released and remains, with pointers to its dummy
arguments
    now dangling.

    The fix adds a condition to avoid the case, and refactors to a new
predicate
    by the way.  Part of the original condition is also removed, for lack of a
    reason to keep it.

            PR fortran/99798

    gcc/fortran/ChangeLog:

            * symbol.cc (gfc_release_symbol): Move the condition guarding
            the handling cyclic references...
            (cyclic_reference_break_needed): ... here as a new predicate.
            Remove superfluous parts.  Add a condition preventing any premature
            release with submodule symbols.

    gcc/testsuite/ChangeLog:

            * gfortran.dg/submodule_33.f08: New test.