[Bug c++/116880] [15 Regression] too early coroutine destruction of co_await on nix-2.24.8

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116880

--- Comment #7 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The trunk branch has been updated by Jason Merrill <jason@gcc.gnu.org>:

https://gcc.gnu.org/g:4c743798b1d4530b327dad7c606c610f3811fdbf

commit r15-7338-g4c743798b1d4530b327dad7c606c610f3811fdbf
Author: Iain Sandoe <iains.gcc@gmail.com>
Date:   Thu Oct 31 08:40:08 2024 +0000

    c++/coroutines: Fix awaiter var creation [PR116506]

    Awaiters always need to have a coroutine state frame copy since
    they persist across potential supensions.  It simplifies the later
    analysis considerably to assign these early which we do when
    building co_await expressions.

    The cleanups in r15-3146-g47dbd69b1, unfortunately elided some of
    processing used to cater for cases where the var created from an
    xvalue, or is a pointer/reference type.

    Corrected thus.

            PR c++/116506
            PR c++/116880

    gcc/cp/ChangeLog:

            * coroutines.cc (build_co_await): Ensure that xvalues are
            materialised.  Handle references/pointer values in awaiter
            access expressions.
            (is_stable_lvalue): New.
            * decl.cc (cxx_maybe_build_cleanup): Handle null arg.

    gcc/testsuite/ChangeLog:

            * g++.dg/coroutines/pr116506.C: New test.
            * g++.dg/coroutines/pr116880.C: New test.

    Signed-off-by: Iain Sandoe <iain@sandoe.co.uk>
    Co-authored-by: Jason Merrill <jason@redhat.com>