[Bug c++/103597] [12 Regression] False -Wimplicit-fallthrough= involving macro since r12-5638-ga3e75c1491cd2d50

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103597

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
For the C++ front-end, we have IF_STMT.

Which is handled in cxx_block_may_fallthru:
    case IF_STMT:
      if (block_may_fallthru (THEN_CLAUSE (stmt)))
        return true;
      return block_may_fallthru (ELSE_CLAUSE (stmt));

-    stmt = else_;
-  else if (integer_nonzerop (cond) && !TREE_SIDE_EFFECTS (else_))
-    stmt = then_;
-  else if (integer_zerop (cond) && !TREE_SIDE_EFFECTS (then_))
-    stmt = else_;

I don't know if this runs counter to again to unreachable code warning
experiment though ...