[Bug c++/120989] New: Shouldn't warn about the use of deprecated non-static data members in implicit special member functions

[iamsupermouse at mail dot ru via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120989

            Bug ID: 120989
           Summary: Shouldn't warn about the use of deprecated non-static
                    data members in implicit special member functions
           Product: gcc
           Version: 14.2.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: iamsupermouse at mail dot ru
  Target Milestone: ---

Here's the testcase:

    struct A
    {
        [[deprecated]] int x = 42;
    };

    int main()
    {
        A a;
        A b = a;
        a = b;
    }

Here GCC warns about `A::x` being deprecated a few times, when it's used in the
implicitly generated special member functions.

I don't think it should warn here, only the manual uses of `x` should be
diagnosed. Clang has the same bug:
https://github.com/llvm/llvm-project/issues/147293 , while MSVC doesn't warn
about this.