Re: [C++ PATCH] Fix make_temporary_var_for_ref_to_temp (PR c++/86669)

[Jason Merrill <jason@redhat.com>]

On 12/6/18 6:26 PM, Jakub Jelinek wrote:
> On Wed, Dec 05, 2018 at 09:50:56PM +0100, Jakub Jelinek wrote:
>> On Wed, Dec 05, 2018 at 03:49:26PM -0500, Jason Merrill wrote:
>>> On 11/28/18 3:42 AM, Jakub Jelinek wrote:
>>>> Whenever we need to clone a cdtor (either because the target doesn't support
>>>> aliases the way we need, e.g. initlist105.C testcase on darwin, where it has
>>>> been originally reported, or when it has virtual bases, like the made up
>>>> initlist106.C on x86_64-linux), we rely on DECL_INITIAL of the local
>>>> variables being unshared, because the tree unsharing gimplify.c performs
>>>> doesn't unshare DECL_INITIAL.  clone_body has some code to recurse on the
>>>> DECL_INITIAL, but it handles just decls FOR_EACH_LOCAL_DECL walks.  I
>>>> believe it is generally ok that not all temporaries are covered in local
>>>> decls, the gimplifier should take care of those fine if we don't need
>>>> debug info for them.
>>>
>>> I think any temporaries that have DECL_INITIAL should be pushed so that they
>>> end up in local_decls.  set_up_extended_ref_temp already adds a DECL_EXPR
>>> for it, I guess we need a pushdecl as well.  Though the comment for
>>> get_temp_regvar suggests that this is problematic somehow.
>>
>> Ok, will play with it tomorrow.
> 
> The following fixes the testcase too and passed bootstrap/regtest on
> x86_64-linux and i686-linux, ok for trunk?
> 
> 2018-12-07  Jakub Jelinek  <jakub@redhat.com>
> 
> 	PR c++/86669
> 	* call.c (make_temporary_var_for_ref_to_temp): Call pushdecl even for
> 	automatic vars.

OK, thanks.

Jason