[PATCH v2 1/2] msvcrt: Clean up registered C++ object in handler.

[Piotr Caban]

Hi Daniel,

On 06/06/17 00:43, Daniel Lehman wrote:
 > +typedef void (CALLBACK *__WINE_FINALLY_CTX)(BOOL, PEXCEPTION_RECORD, 
void*);
The idea behind __FINALLY_CTX was to model native __finally behavior 
while extending its functionality for wine. It's not possible to call 
GetExceptionInfo/GetExceptionCode inside of finally on Windows so I 
don't think it's a change in good direction. If you really need the 
exception record you shouldn't use __FINALLY_CTX (but I don't think you 
need).

> +static void CALLBACK cxx_catch_cleanup(BOOL normal, EXCEPTION_RECORD *rec, void *ctx)
> +{
> +    thread_data_t *data = msvcrt_get_thread_data();
> +    cxx_frame_info *frame = ctx;
> +
> +    if (normal)
> +        __CxxUnregisterExceptionObject(frame, FALSE);
> +    else
> +    {
> +        if (cxx_is_consolidate(rec))
> +            rec = (void*)rec->ExceptionInformation[4];
> +
> +        __CxxUnregisterExceptionObject(frame,
> +                rec->ExceptionCode == CXX_EXCEPTION &&
> +                data->exc_record->ExceptionCode == CXX_EXCEPTION &&
> +                rec->ExceptionInformation[1] == data->exc_record->ExceptionInformation[1]);
> +    }
Do you need to call __CxxUnregisterExceptionObject with TRUE as second 
argument in any case except of rethrow?

>       /* FIXME:  native does local_unwind here in case of exception rethrow */
If you only need to handle rethrow in a special way I think it should be 
done differently. Something like this should do the job:
__TRY
{
     __TRY
     {
         ret_addr = handler(0, frame);
     }
     __EXCEPT(rethrow_filter)
     {
         /* probably all of this should be done inside  of the filter */
	/* do some unwinding here or add a FIXME */
         catch_cleanup_ctx.in_use = TRUE;
         rethrow;
     }
     __ENDTRY;
}
__FINALLY_CTX(cxx_catch_cleanup, &catch_cleanup_ctx);

The above code is incorrect if exception object needs to be preserved 
not only in case of rethrow.

What do you think about it?

Thanks,
Piotr