[Bug c++/51868] New: Crash when generating the move constructor for a class with a bit field

[Bug c++/51868] New: Crash when generating the move constructor for a class with a bit field

[ogoffart at kde dot org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51868

             Bug #: 51868
           Summary: Crash when generating the move constructor for a class
                    with a bit field
    Classification: Unclassified
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: ogoffart@kde.org


Created attachment 26341
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=26341
testcase

See the attached example.
Compilation flag used: -std=c++0x

gcc crashes with:

bitfield.cc: In constructor ‘B::B(B&&)’:
bitfield.cc:7:8: internal compiler error: Segmentation fault
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.

Reproduced with GCC 4.6.2 from archlinux binary package, and gcc 4.7 from
trunk.
Used to work with GCC 4.6.1

[Bug c++/51868] [4.7 Regression] Crash when generating the move constructor for a class with a bit field

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51868

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2012-01-16
      Known to work|                            |4.6.2
            Summary|Crash when generating the   |[4.7 Regression] Crash when
                   |move constructor for a      |generating the move
                   |class with a bit field      |constructor for a class
                   |                            |with a bit field
     Ever Confirmed|0                           |1
      Known to fail|                            |4.7.0

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> 2012-01-16 14:36:58 UTC ---
Confirmed with 4.7, it works with 4.6.1 and 4.6.2

IIRC Arch Linux lies about the version, what they call 4.6.2 is the unreleased
4.6.3, so please provide the output of gcc -v as requested by the URL you
quoted.

[Bug c++/51868] [4.7 Regression] Crash when generating the move constructor for a class with a bit field

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51868

--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> 2012-01-16 14:45:33 UTC ---
on trunk:

Program received signal SIGSEGV, Segmentation fault.
fold_convert_loc (loc=0, type=0x2aaaaac5da80, arg=0x0) at
/home/redi/src/gcc/gcc-4.7-20120114/gcc/fold-const.c:1856
1856      tree orig = TREE_TYPE (arg);

[Bug c++/51868] [4.7 Regression] Crash when generating the move constructor for a class with a bit field

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51868

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                     |

[Bug c++/51868] [4.7 Regression] Crash when generating the move constructor for a class with a bit field

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51868

--- Comment #3 from Jason Merrill <jason at gcc dot gnu.org> 2012-01-16 18:40:33 UTC ---
Author: jason
Date: Mon Jan 16 18:40:26 2012
New Revision: 183218

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=183218
Log:
    PR c++/51868
    * typeck.c (build_static_cast_1): Handle bit-fields properly.

Added:
    trunk/gcc/testsuite/g++.dg/cpp0x/rv-bitfield.C
    trunk/gcc/testsuite/g++.dg/cpp0x/rv-bitfield2.C
Modified:
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/typeck.c
    trunk/gcc/testsuite/ChangeLog

[Bug c++/51868] [4.7 Regression] Crash when generating the move constructor for a class with a bit field

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51868

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

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

--- Comment #4 from Jason Merrill <jason at gcc dot gnu.org> 2012-01-16 18:54:47 UTC ---
Fixed.

[Bug c++/51868] [4.7 Regression] Crash when generating the move constructor for a class with a bit field

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51868

--- Comment #5 from Jonathan Wakely <redi at gcc dot gnu.org> 2012-01-16 18:57:59 UTC ---
Jason, does it happen with 4.6.3 too?  I couldn't test that

[Bug c++/51868] [4.6 Regression] Crash when generating the move constructor for a class with a bit field

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51868

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|RESOLVED                    |ASSIGNED
         Resolution|FIXED                       |
            Summary|[4.7 Regression] Crash when |[4.6 Regression] Crash when
                   |generating the move         |generating the move
                   |constructor for a class     |constructor for a class
                   |with a bit field            |with a bit field

--- Comment #6 from Jason Merrill <jason at gcc dot gnu.org> 2012-01-16 21:13:38 UTC ---
Yes, it also breaks with the current 4.6 branch; I'll apply the fix there as
well.

[Bug c++/51868] [4.6 Regression] Crash when generating the move constructor for a class with a bit field

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51868

--- Comment #7 from Jason Merrill <jason at gcc dot gnu.org> 2012-01-16 21:34:30 UTC ---
Author: jason
Date: Mon Jan 16 21:34:26 2012
New Revision: 183223

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=183223
Log:
    PR c++/51868
    * typeck.c (build_static_cast_1): Handle bit-fields properly.

Added:
    branches/gcc-4_6-branch/gcc/testsuite/g++.dg/cpp0x/rv-bitfield.C
    branches/gcc-4_6-branch/gcc/testsuite/g++.dg/cpp0x/rv-bitfield2.C
Modified:
    branches/gcc-4_6-branch/gcc/cp/ChangeLog
    branches/gcc-4_6-branch/gcc/cp/typeck.c
    branches/gcc-4_6-branch/gcc/testsuite/ChangeLog

[Bug c++/51868] [4.6 Regression] Crash when generating the move constructor for a class with a bit field

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51868

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|4.7.0                       |4.6.3

--- Comment #8 from Jason Merrill <jason at gcc dot gnu.org> 2012-01-16 21:37:29 UTC ---
Fixed for 4.6.3 as well.