[Bug c++/49267] New: Ambiguity with conversion functions "T&" and "T&&", initializing a "T&&"

[Bug c++/49267] New: Ambiguity with conversion functions "T&" and "T&&", initializing a "T&&"

[schaub.johannes at googlemail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49267

           Summary: Ambiguity with conversion functions "T&" and "T&&",
                    initializing a "T&&"
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: schaub.johannes@googlemail.com


This is ambiguous with GCC, but probably should select the "T&":

    struct X {
      operator int&();
      operator int&&();
    };

    int&&x = X();

GCC says:

main1.cpp:7:16: error: conversion from ‘X’ to ‘int’ is ambiguous
main1.cpp:7:16: note: candidates are:
main1.cpp:4:7: note: X::operator int&&()
main1.cpp:3:7: note: X::operator int&()

[Bug c++/49267] Ambiguity with conversion functions "T&" and "T&&", initializing a "T&&"

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49267

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
   Last reconfirmed|                            |2011-09-04
         AssignedTo|unassigned at gcc dot       |jason at gcc dot gnu.org
                   |gnu.org                     |
   Target Milestone|---                         |4.7.0
     Ever Confirmed|0                           |1

[Bug c++/49267] Ambiguity with conversion functions "T&" and "T&&", initializing a "T&&"

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49267

--- Comment #2 from Jason Merrill <jason at gcc dot gnu.org> 2011-09-05 04:34:01 UTC ---
Author: jason
Date: Mon Sep  5 04:33:57 2011
New Revision: 178521

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=178521
Log:
    PR c++/49267
    * call.c (reference_binding): Don't set is_lvalue for an rvalue
    reference rfrom.

Modified:
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/call.c

[Bug c++/49267] Ambiguity with conversion functions "T&" and "T&&", initializing a "T&&"

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49267

--- Comment #1 from Jason Merrill <jason at gcc dot gnu.org> 2011-09-05 04:33:53 UTC ---
Author: jason
Date: Mon Sep  5 04:33:48 2011
New Revision: 178520

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=178520
Log:
    PR c++/49267
    PR c++/49458
    DR 1328
    * call.c (reference_binding): Set rvaluedness_matches_p properly
    for reference to function conversion ops.
    (compare_ics): Adjust.

Added:
    trunk/gcc/testsuite/g++.dg/cpp0x/rv-conv1.C
    trunk/gcc/testsuite/g++.dg/cpp0x/rv-func3.C
Modified:
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/call.c
    trunk/gcc/testsuite/ChangeLog

[Bug c++/49267] Ambiguity with conversion functions "T&" and "T&&", initializing a "T&&"

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49267

--- Comment #3 from Jason Merrill <jason at gcc dot gnu.org> 2011-09-05 15:44:06 UTC ---
Author: jason
Date: Mon Sep  5 15:43:58 2011
New Revision: 178552

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=178552
Log:
    PR c++/49267
    * call.c (compare_ics): rvaluedness_matches_p can differ
    based on the source type, not just target.

Added:
    branches/gcc-4_6-branch/gcc/testsuite/g++.dg/cpp0x/rv-conv1.C
Modified:
    branches/gcc-4_6-branch/gcc/cp/ChangeLog
    branches/gcc-4_6-branch/gcc/cp/call.c
    branches/gcc-4_6-branch/gcc/testsuite/ChangeLog

[Bug c++/49267] Ambiguity with conversion functions "T&" and "T&&", initializing a "T&&"

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49267

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|4.7.0                       |4.6.2

--- Comment #4 from Jason Merrill <jason at gcc dot gnu.org> 2011-09-05 15:45:32 UTC ---
Fixed for 4.6.2.

[Bug c++/49267] Ambiguity with conversion functions "T&" and "T&&", initializing a "T&&"

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49267

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.6.2                       |4.7.0

--- Comment #6 from Jason Merrill <jason at gcc dot gnu.org> 2011-09-17 22:37:08 UTC ---
The fix in 4.6.2 caused bug 50442, so I've reverted it; still fixed for 4.7.

[Bug c++/49267] Ambiguity with conversion functions "T&" and "T&&", initializing a "T&&"

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49267

--- Comment #5 from Jason Merrill <jason at gcc dot gnu.org> 2011-09-17 22:35:15 UTC ---
Author: jason
Date: Sat Sep 17 22:35:10 2011
New Revision: 178932

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=178932
Log:
    PR c++/50442
    Revert:
    PR c++/49267
    * call.c (compare_ics): rvaluedness_matches_p can differ
    based on the source type, not just target.

Removed:
    branches/gcc-4_6-branch/gcc/testsuite/g++.dg/cpp0x/rv-conv1.C
Modified:
    branches/gcc-4_6-branch/gcc/cp/ChangeLog
    branches/gcc-4_6-branch/gcc/cp/call.c
    branches/gcc-4_6-branch/gcc/testsuite/ChangeLog