[Bug c++/56222] New: Pointer to member in lambda should not require this to be captured

[Bug c++/56222] New: Pointer to member in lambda should not require this to be captured

[boris.bigott at hotmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56222

             Bug #: 56222
           Summary: Pointer to member in lambda should not require this to
                    be captured
    Classification: Unclassified
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: boris.bigott@hotmail.com


In the example below, gcc complains about this not being captures. This happens
whenever a pointer to a member function is requested in a lambda. I tested with
gcc-4.7.2.

struct Test {
    void y() { }
    void x() {
        [](Test &t) { (t.*(&Test::y))(); }(*this);
    }
};  

int main() {  Test().x(); }

[Bug c++/56222] Pointer to member in lambda should not require this to be captured

[paolo.carlini at oracle dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56222

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |daniel.kruegler at
                   |                            |googlemail dot com

--- Comment #1 from Paolo Carlini <paolo.carlini at oracle dot com> 2013-02-06 11:32:40 UTC ---
I don't think this is legal, when y isn't static I mean (otherwise it would be
a dup of PR55828). Daniel, what do you think?

[Bug c++/56222] Pointer to member in lambda should not require this to be captured

[daniel.kruegler at googlemail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56222

--- Comment #2 from Daniel Krügler <daniel.kruegler at googlemail dot com> 2013-02-06 11:42:21 UTC ---
The code looks valid to me, I don't see any reason for capturing something
here. The expression "&Test::y" should be valid in that scope and returns an
rvalue.

[Bug c++/56222] Pointer to member in lambda should not require this to be captured

[paolo.carlini at oracle dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56222

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2013-02-06
             Blocks|                            |54367
     Ever Confirmed|0                           |1

--- Comment #3 from Paolo Carlini <paolo.carlini at oracle dot com> 2013-02-06 11:55:51 UTC ---
Ok, confirmed.

[Bug c++/56222] Pointer to member in lambda should not require this to be captured

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56222

Jason Merrill <jason at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
                 CC|                            |jason at gcc dot gnu.org
         AssignedTo|unassigned at gcc dot       |jason at gcc dot gnu.org
                   |gnu.org                     |

--- Comment #4 from Jason Merrill <jason at gcc dot gnu.org> 2013-03-05 17:46:53 UTC ---
Related to 51494.

[Bug c++/56222] Pointer to member in lambda should not require this to be captured

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56222

--- Comment #5 from Jason Merrill <jason at gcc dot gnu.org> 2013-03-08 16:03:57 UTC ---
Author: jason
Date: Fri Mar  8 16:03:48 2013
New Revision: 196549

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=196549
Log:
    PR c++/51494
    PR c++/51884
    PR c++/56222
    * tree.c (maybe_dummy_object): Don't capture 'this'.
    * semantics.c (maybe_resolve_dummy): New.
    (finish_non_static_data_member): Use it.
    (finish_qualified_id_expr): Don't test is_dummy_object.
    * cp-tree.h: Declare maybe_resolve_dummy.
    * call.c (build_new_method_call_1): Use it.

Added:
    trunk/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-this11.C
Modified:
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/call.c
    trunk/gcc/cp/cp-tree.h
    trunk/gcc/cp/semantics.c
    trunk/gcc/cp/tree.c

[Bug c++/56222] Pointer to member in lambda should not require this to be captured

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56222

Jason Merrill <jason at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|---                         |4.8.0

--- Comment #6 from Jason Merrill <jason at gcc dot gnu.org> 2013-03-08 16:09:29 UTC ---
Fixed for 4.8.

[Bug c++/56222] Pointer to member in lambda should not require this to be captured

[bruck.michael at googlemail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56222

Michael Bruck <bruck.michael at googlemail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |bruck.michael at googlemail
                   |                            |dot com

--- Comment #7 from Michael Bruck <bruck.michael at googlemail dot com> 2013-03-17 21:12:24 UTC ---
This issue applies to 4.7.x too. Any chance to get this backported?

[Bug c++/56222] Pointer to member in lambda should not require this to be captured

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56222

--- Comment #8 from Jason Merrill <jason at gcc dot gnu.org> 2013-03-18 03:51:11 UTC ---
Now that 4.8.0 is about to be released, I'm reluctant to backport
non-regression C++11 fixes to 4.7.