On 11/19/23 02:38, Alexandre Oliva wrote:
__dt_base doesn't get its body from a maybe_return_this caller, it's rather cloned with the full body within build_clone, and then it's left alone, without going through finish_function_body or build_delete_destructor_body, that call maybe_return_this. Now, this is correct as far as the generated code is concerned, since the cloned body of a cdtor that returns this is also a cdtor body that returns this. The problem is that the decl for THIS is also cloned, and it doesn't get the warning suppression introduced by maybe_return_this, so Wuse-after-free3.C fails with an excess warning at the closing brace of the dtor body. I've split out the warning suppression from maybe_return_this, and arranged to call that bit from the relevant build_clone case. Unfortunately, because the warning is silenced for all uses of the THIS decl, rather than only for the ABI-mandated return stmt, this also silences the very warning that the testcase checks for. I'm not revamping the warning suppression approach to overcome this, so I'm xfailing the expected warning on ARM EABI, hoping that's the only target with cdtor_return_this, and leaving it at that.
So it only passed on that platform before because of the bug?
Regstrapped on x86_64-linux-gnu, also tested on arm-eabi with default cpu on trunk, and with tms570 on gcc-13. Ok to install?
OK. Jason
