[Bug libstdc++/105387] libstdc++: with -fno-rtti, pointer type info class incorrectly matches non-pointer type info classes

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105387

--- Comment #4 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Jonathan Wakely <redi@gcc.gnu.org>:

https://gcc.gnu.org/g:b83f01d0057578ebc1785f858fbfd46cdc210560

commit r13-3696-gb83f01d0057578ebc1785f858fbfd46cdc210560
Author: Jakob Hasse <0xjakob@users.noreply.github.com>
Date:   Tue Apr 26 12:03:47 2022 +0800

    libstdc++: fix pointer type exception catch (no RTTI) [PR105387]

    __pbase_type_info::__do_catch(), used to catch pointer type exceptions,
    did not check if the type info object to compare against is a pointer
    type info object before doing a static down-cast to a pointer type info
    object. If RTTI is disabled, this leads to the following situation:
    Since a pointer type info object has additional fields, they would
    end up being undefined if the actual type info object was not a pointer
    type info object.

    A simple check has been added before the down-cast happens.

    Note that a consequence of this check is that exceptions of type
    pointer-to-member cannot be caught anymore.

    In case RTTI is enabled, this does not seem to be a problem because
    RTTI-based checks would run before and prevent running into the bad
    down-cast. Hence, the fix is disabled if RTTI is enabled and exceptions
    of type pointer-to-member can still be caught.

    libstdc++-v3/ChangeLog:

            PR libstdc++/105387
            * libsupc++/pbase_type_info.cc (__do_catch) [!__cpp_rtti]: Add
            check that the thrown type is actually a pointer.
            * testsuite/18_support/105387.cc: New test.
            * testsuite/18_support/105387_memptr.cc: New test.

    Signed-off-by: Jakob Hasse <jakob.hasse@espressif.com>