[Bug libstdc++/101659] _GLIBCXX_DEBUG mode for std::optional ?

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101659

--- Comment #5 from GCC 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:eb2c12561c10f78e03b4eb63685f937a107305f0

commit r15-2304-geb2c12561c10f78e03b4eb63685f937a107305f0
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Mon Jul 22 20:24:19 2024 +0100

    libstdc++: Move std::optional assertions out of _M_get()

    Currently we implement the precondition for accessing the contained
    value of a std::optional in the _M_get() accessor in the base class.
    This means that we always check the assertions even in internal
    functions that have an explicit check for a contained value being
    present, such as value() and value_or(U&&). Although those redundant
    assertions should get optimized out in most cases, they might hurt
    inliner heuristics and generally give the compiler more work to do.
    And they won't be optimized out at all for non-optimized builds.

    The current assertions also result in repeated invalid bug reports, such
    as PR 91281, PR 101659, PR 102712, and PR 107894.

    We can move the assertions from the internal accessors to the public
    member functions where the preconditions are specified.

    Reviewed-by: Ville Voutilainen <ville.voutilainen@gmail.com>

    libstdc++-v3/ChangeLog:

            * include/std/optional (_Optional_base_impl::_M_get()): Move
            assertions to ...
            (optional::operator->, optional::operator*): ... here.