Re: [PR c++/78469] default ctor makes dtor required

[Jason Merrill <jason at redhat dot com>]

On 01/24/2017 09:13 AM, Nathan Sidwell wrote:
> On 01/23/2017 05:01 PM, Jason Merrill wrote:
>
> > I suppose adding a tsubst flag isn't too horrible.  But then we also
> > need to audit other uses of build_value_init to decide whether they
> > should build a cleanup or not.

> @@ -8055,7 +8055,8 @@ build_over_call (struct z_candidate *can
>        else if (default_ctor_p (fn))
>  	{
>  	  if (is_dummy_object (argarray[0]))
> -	    return force_target_expr (DECL_CONTEXT (fn), void_node, complain);
> +	    return force_target_expr (DECL_CONTEXT (fn), void_node,
> +				      complain | tf_no_cleanup);

This is the wrong place for this; we don't know at this point whether 
we're in a new-expression or actually creating a temporary.  I think we 
want to add this flag in the call to build_value_init from build_new_1. 
And look at other calls to build_value_init to see if they want it as well.

Jason