[Bug c++/59012] New: alignas does not support parameter pack expansions

[Bug c++/59012] New: alignas does not support parameter pack expansions

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59012

            Bug ID: 59012
           Summary: alignas does not support parameter pack expansions
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Keywords: rejects-valid
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: redi at gcc dot gnu.org
            Blocks: 58601

template<unsigned N, typename... T>
struct aligned_union
{
  alignas(T...) char data[N];
};

int main()
{
  aligned_union<8, double> a;
}

[Bug c++/59012] alignas does not support parameter pack expansions

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59012

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Version|unknown                     |4.9.0

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
a.cc:4:12: error: expected ‘)’ before ‘...’ token
   alignas(T...) char data[N];
            ^
a.cc:4:12: error: expected ‘)’ before ‘...’ token
a.cc:4:12: error: expected unqualified-id before ‘...’ token
>From gcc-bugs-return-433659-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org Tue Nov 05 19:51:14 2013
Return-Path: <gcc-bugs-return-433659-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org>
Delivered-To: listarch-gcc-bugs@gcc.gnu.org
Received: (qmail 9061 invoked by alias); 5 Nov 2013 19:51:13 -0000
Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm
Precedence: bulk
List-Id: <gcc-bugs.gcc.gnu.org>
List-Archive: <http://gcc.gnu.org/ml/gcc-bugs/>
List-Post: <mailto:gcc-bugs@gcc.gnu.org>
List-Help: <mailto:gcc-bugs-help@gcc.gnu.org>
Sender: gcc-bugs-owner@gcc.gnu.org
Delivered-To: mailing list gcc-bugs@gcc.gnu.org
Received: (qmail 7355 invoked by uid 48); 5 Nov 2013 19:49:10 -0000
From: "pault at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug fortran/55574] [4.7/4.8 Regression] C binding access to c_ptr type
Date: Tue, 05 Nov 2013 19:51:00 -0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: fortran
X-Bugzilla-Version: 4.8.0
X-Bugzilla-Keywords: accepts-invalid, diagnostic
X-Bugzilla-Severity: minor
X-Bugzilla-Who: pault at gcc dot gnu.org
X-Bugzilla-Status: NEW
X-Bugzilla-Priority: P4
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: 4.7.4
X-Bugzilla-Flags:
X-Bugzilla-Changed-Fields: cc
Message-ID: <bug-55574-4-9DrkIox5Of@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-55574-4@http.gcc.gnu.org/bugzilla/>
References: <bug-55574-4@http.gcc.gnu.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 7bit
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
X-SW-Source: 2013-11/txt/msg00436.txt.bz2
Content-length: 889

http://gcc.gnu.org/bugzilla/show_bug.cgi?idU574

Paul Thomas <pault at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |pault at gcc dot gnu.org

--- Comment #7 from Paul Thomas <pault at gcc dot gnu.org> ---
(In reply to Mikael Morin from comment #6)
> This is fixed on trunk (upcoming 4.9.0).
>
> As Tobias' fix is somewhat intrusive, another patch which I posted at
> http://gcc.gnu.org/ml/fortran/2013-03/msg00008.html
> was considered for 4.8 and 4.7 backport.
>
> But this will probably end up with a WONTFIX for the branches.

Hi Mikael,

I have only returned to the fray in the last week or two.

Tell me, why was your patch never applied?  As far as I can see, nobody even
reviewed it - is that right?

Cheers

Paul

[Bug c++/59012] alignas does not support parameter pack expansions

[paolo.carlini at oracle dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59012

Paolo Carlini <paolo.carlini at oracle dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2013-11-06
     Ever confirmed|0                           |1

--- Comment #2 from Paolo Carlini <paolo.carlini at oracle dot com> ---
Looks like quite a bit is unimplemented about this, both in the parser and in
pt.c. I mean to have a look.

[Bug c++/59012] alignas does not support parameter pack expansions

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59012

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |filip.roseen at gmail dot com

--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> ---
*** Bug 62136 has been marked as a duplicate of this bug. ***

[Bug c++/59012] alignas does not support parameter pack expansions

[jason at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59012

--- Comment #4 from Jason Merrill <jason at gcc dot gnu.org> ---
Author: jason
Date: Fri May  8 04:42:06 2015
New Revision: 222902

URL: https://gcc.gnu.org/viewcvs?rev=222902&root=gcc&view=rev
Log:
        PR c++/59012
        * parser.c (cp_parser_std_attribute_list): Handle attribute expansion.
        (cp_parser_std_attribute_spec): Handle alignas pack expansion.
        * decl2.c (is_late_template_attribute): An attribute exp is dependent.
        * pt.c (make_pack_expansion): Allow TREE_LIST for attribute expansion.
        (apply_late_template_attributes): Handle attribute pack expansion.

Added:
    trunk/gcc/testsuite/g++.dg/cpp0x/alignas4.C
Modified:
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/decl2.c
    trunk/gcc/cp/parser.c
    trunk/gcc/cp/pt.c

[Bug c++/59012] alignas does not support parameter pack expansions

[jason at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59012

--- Comment #5 from Jason Merrill <jason at gcc dot gnu.org> ---
Author: jason
Date: Fri May  8 21:15:21 2015
New Revision: 222927

URL: https://gcc.gnu.org/viewcvs?rev=222927&root=gcc&view=rev
Log:
        PR c++/59012
        * parser.c (cp_parser_std_attribute_list): Handle attribute expansion.
        (cp_parser_std_attribute_spec): Handle alignas pack expansion.
        * decl2.c (is_late_template_attribute): An attribute exp is dependent.
        * pt.c (make_pack_expansion): Allow TREE_LIST for attribute expansion.
        (apply_late_template_attributes): Handle attribute pack expansion.

Added:
    branches/gcc-5-branch/gcc/testsuite/g++.dg/cpp0x/alignas4.C
Modified:
    branches/gcc-5-branch/gcc/cp/ChangeLog
    branches/gcc-5-branch/gcc/cp/decl2.c
    branches/gcc-5-branch/gcc/cp/parser.c
    branches/gcc-5-branch/gcc/cp/pt.c

[Bug c++/59012] alignas does not support parameter pack expansions

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59012

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |5.2