[Bug c++/104066] "constinit extern long (*const f) ();" doesn't compile: gcc thinks "constinit" applies to return value, not to function pointer itself

[cvs-commit at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104066

--- Comment #5 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-12 branch has been updated by Marek Polacek
<mpola...@gcc.gnu.org>:

https://gcc.gnu.org/g:14faa5f585f6025df1e04c8c8b34340ff5e4d494

commit r12-8916-g14faa5f585f6025df1e04c8c8b34340ff5e4d494
Author: Marek Polacek <pola...@redhat.com>
Date:   Thu Nov 17 11:59:29 2022 -0500

    c++: constinit on pointer to function [PR104066]

    [dcl.constinit]: "The constinit specifier shall be applied only to
    a declaration of a variable with static or thread storage duration."

    Thus, this ought to be OK:

      constinit void (*p)() = nullptr;

    but the error message I introduced when implementing constinit was
    not looking at funcdecl_p, so the code above was rejected.

    Fixed thus.  I'm checking constinit_p first because I think that's
    far more likely to be false than funcdecl_p.

            PR c++/104066

    gcc/cp/ChangeLog:

            * decl.cc (grokdeclarator): Check funcdecl_p before complaining
            about constinit.

    gcc/testsuite/ChangeLog:

            * g++.dg/cpp2a/constinit18.C: New test.

    (cherry picked from commit 7b3b2f50953c5143d4b14b59d322d8a793f411dd)