[Bug c++/81660] Add -Wexceptions warning

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81660

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

https://gcc.gnu.org/g:43d3b7bc073df27800218b685e6d7dd78dd31905

commit r11-4803-g43d3b7bc073df27800218b685e6d7dd78dd31905
Author: Marek Polacek <polacek@redhat.com>
Date:   Thu Nov 5 21:46:06 2020 -0500

    c++: Small tweak to can_convert_eh [PR81660]

    While messing with check_handlers_1, I spotted this bug report which
    complains that we don't warn about the case when we have two duplicated
    handlers of type int.  can_convert_eh implements [except.handle] and
    that says: A handler is a match for an exception object of type E if
     - The handler is of type cv T or cv T& and E and T are the same type
       (ignoring the top-level cv-qualifiers), or [...]

    but we don't implement this bullet properly for non-class types.  The
    fix therefore seems pretty obvious.  Also change the return type to
    bool when we're only returning yes/no.

    gcc/cp/ChangeLog:

            PR c++/81660
            * except.c (can_convert_eh): Change the return type to bool.  If
            the type TO and FROM are the same, return true.

    gcc/testsuite/ChangeLog:

            PR c++/81660
            * g++.dg/warn/Wexceptions3.C: New test.
            * g++.dg/eh/pr42859.C: Add dg-warning.
            * g++.dg/torture/pr81659.C: Likewise.