[Bug c++/114777] New: inconsistent warning for pure functions on deconstructors/constructors on arm compared to other targets

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114777

            Bug ID: 114777
           Summary: inconsistent warning for pure functions on
                    deconstructors/constructors on arm compared to other
                    targets
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Keywords: diagnostic
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: pinskia at gcc dot gnu.org
  Target Milestone: ---
            Target: arm-eabi, arm-linux-gnueabi

Take:
```
struct A {
    A();
    [[gnu::pure]] ~A();
};
```

This warns on all targets except for arm-eabi (and arm-linux-gnueabi) due to
having targetm.cxx.cdtor_returns_this() return true.

I only noticed this while working on PR 19661 .