[Bug c++/110468] [12/13/14 regression] Internal compiler error in nothrow_spec_p

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110468

--- Comment #14 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-13 branch has been updated by Patrick Palka
<ppalka@gcc.gnu.org>:

https://gcc.gnu.org/g:23c64450cbce916547142519a72075d1930c8282

commit r13-7517-g23c64450cbce916547142519a72075d1930c8282
Author: Patrick Palka <ppalka@redhat.com>
Date:   Thu Jun 29 16:10:18 2023 -0400

    c++: NSDMI instantiation during overload resolution [PR110468]

    Here we find ourselves instantiating the NSDMI for A<1>::m when
    computing argument conversions during overload resolution, and
    thus tf_conv is set.  The flag causes mark_used for the constructor
    used in the NSDMI to exit early and not instantiate its noexcept-spec,
    which eventually leads to an ICE from nothrow_spec_p.

    This patch fixes this by clearing any special tsubst flags during
    instantiation of an NSDMI, since the result should be independent of
    the context that requires the instantiation.

            PR c++/110468

    gcc/cp/ChangeLog:

            * init.cc (maybe_instantiate_nsdmi_init): Mask out all
            tsubst flags except for tf_warning_or_error.

    gcc/testsuite/ChangeLog:

            * g++.dg/cpp0x/noexcept79.C: New test.

    (cherry picked from commit 9479da4515f7d019b4ef282d0e21536431c44f71)