[Bug middle-end/49545] New: [4.7 Regression] New C++ test failures

[Bug middle-end/49545] New: [4.7 Regression] New C++ test failures

[hjl.tools at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49545

           Summary: [4.7 Regression] New C++ test failures
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: hjl.tools@gmail.com
                CC: rguenther@suse.de


On Linux/x86, revision 175427:

http://gcc.gnu.org/ml/gcc-cvs/2011-06/msg00918.html

caused:

FAIL: g++.dg/cpp0x/constexpr-ptrmem.C (test for excess errors)
FAIL: g++.dg/tree-ssa/fwprop-align.C scan-tree-dump-times forwprop2 "& 1" 0

[Bug middle-end/49545] [4.7 Regression] New C++ test failures

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49545

--- Comment #2 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-06-27 13:36:03 UTC ---
An anyway useful transform would be to hoist the call in

  iftmp.0_15 = *D.2099_14;

<bb 4>:
  # iftmp.0_1 = PHI <foo(2), iftmp.0_15(3)>
  iftmp.0_1 (&a);

based on the fact that on the edge 2->4 it will be a direct call.

[Bug middle-end/49545] [4.7 Regression] New C++ test failures

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49545

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2011.06.27 13:22:25
   Target Milestone|---                         |4.7.0
     Ever Confirmed|0                           |1

--- Comment #1 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-06-27 13:22:25 UTC ---
Ugh, I think at least g++.dg/tree-ssa/fwprop-align.C is bogus when it tries
to use alignment to compute whether a indicator bit is set ...

Anyway, confirmed.

[Bug middle-end/49545] [4.7 Regression] New C++ test failures

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49545

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jason at gcc dot gnu.org,
                   |                            |rsandifo at gcc dot gnu.org

--- Comment #3 from Jason Merrill <jason at gcc dot gnu.org> 2011-06-28 06:31:11 UTC ---
constexpr-ptrmem.C is now failing because the C++ ABI uses the low bit of the
function pointer field in a pointer-to-member function to indicate whether that
field is actually a function pointer or a vtable index, and constexpr-ptrmem.C
relies on being able to fold (&fn) & 1 to 0.

I assume that the ARM C++ ABI variant uses a different representation.

[Bug middle-end/49545] [4.7 Regression] New C++ test failures

[rsandifo at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49545

rsandifo@gcc.gnu.org <rsandifo at gcc dot gnu.org> changed:

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

--- Comment #4 from rsandifo at gcc dot gnu.org <rsandifo at gcc dot gnu.org> 2011-06-28 09:42:34 UTC ---
Sorry for the breakage.  I should obviously have tested
on x86_64-linux-gnu as well.

[Bug middle-end/49545] [4.7 Regression] New C++ test failures

[hp at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49545

Hans-Peter Nilsson <hp at gcc dot gnu.org> changed:

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

--- Comment #5 from Hans-Peter Nilsson <hp at gcc dot gnu.org> 2011-06-28 13:07:34 UTC ---
yup, cris-elf (non-strict-alignment) too...

[Bug middle-end/49545] [4.7 Regression] New C++ test failures

[rsandifo at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49545

--- Comment #6 from rsandifo at gcc dot gnu.org <rsandifo at gcc dot gnu.org> 2011-06-29 09:42:46 UTC ---
Author: rsandifo
Date: Wed Jun 29 09:42:42 2011
New Revision: 175627

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=175627
Log:
gcc/
    PR tree-optimization/49545
    * builtins.c (get_object_alignment_1): Update function comment.
    Do not use DECL_ALIGN for functions, but test
    TARGET_PTRMEMFUNC_VBIT_LOCATION instead.
    * fold-const.c (get_pointer_modulus_and_residue): Don't check
    for functions here.
    * tree-ssa-ccp.c (get_value_from_alignment): Likewise.

gcc/testsuite/
    * gcc.dg/torture/pr49169.c: Restrict to ARM and MIPS targets.

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/builtins.c
    trunk/gcc/fold-const.c
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gcc.dg/torture/pr49169.c
    trunk/gcc/tree-ssa-ccp.c

[Bug middle-end/49545] [4.7 Regression] New C++ test failures

[uweigand at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49545

Ulrich Weigand <uweigand at gcc dot gnu.org> changed:

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

--- Comment #7 from Ulrich Weigand <uweigand at gcc dot gnu.org> 2011-07-15 12:51:20 UTC ---
I'm now seeing
FAIL: g++.dg/tree-ssa/fwprop-align.C scan-tree-dump-times forwprop2 "& 1" 0
on the 4.6 branch for spu-elf ...

Could this be the same problem?

[Bug middle-end/49545] [4.7 Regression] New C++ test failures

[danglin at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49545

John David Anglin <danglin at gcc dot gnu.org> changed:

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

--- Comment #8 from John David Anglin <danglin at gcc dot gnu.org> 2011-07-17 16:48:34 UTC ---
I'm also seeing it on hppa64-hp-hpux11.11.

[Bug middle-end/49545] [4.6 Regression] New C++ test failures

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49545

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to work|                            |4.7.0
   Target Milestone|4.7.0                       |4.6.2
            Summary|[4.7 Regression] New C++    |[4.6 Regression] New C++
                   |test failures               |test failures

--- Comment #9 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-07-18 08:12:50 UTC ---
Can you check what patch caused it on the 4.6 branch?  I suppose "fixed" on
the trunk.

[Bug middle-end/49545] [4.6 Regression] New C++ test failures

[uweigand at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49545

--- Comment #10 from Ulrich Weigand <uweigand at gcc dot gnu.org> 2011-07-18 14:35:44 UTC ---
(In reply to comment #9)
> Can you check what patch caused it on the 4.6 branch?

It is this one:
http://gcc.gnu.org/ml/gcc-cvs/2011-07/msg00431.html

2011-07-11  Martin Jambor  <mjambor@suse.cz>

    PR tree-optimization/49094
    * tree-sra.c (tree_non_mode_aligned_mem_p): New function.
    (build_accesses_from_assign): Use it.

> I suppose "fixed" on the trunk.

Yes, that's correct.

[Bug middle-end/49545] [4.6 Regression] New C++ test failures

[hp at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49545

--- Comment #11 from Hans-Peter Nilsson <hp at gcc dot gnu.org> 2011-07-22 14:01:50 UTC ---
Looks like this got "unfixed" on trunk?
It worked on r176507, had reappeared on r176524.

[Bug middle-end/49545] [4.6 Regression] New C++ test failures

[uweigand at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49545

--- Comment #12 from Ulrich Weigand <uweigand at gcc dot gnu.org> 2011-07-28 08:43:31 UTC ---
After this commit:
http://gcc.gnu.org/ml/gcc-cvs/2011-07/msg01132.html
the regression is now gone again on the 4.6 branch.

On spu-elf, this bug is now fixed both on mainline and the 4.6.

[Bug middle-end/49545] [4.6 Regression] New C++ test failures

[hp at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49545

--- Comment #13 from Hans-Peter Nilsson <hp at gcc dot gnu.org> 2011-07-28 14:56:33 UTC ---
(In reply to comment #12)
> After this commit:
> http://gcc.gnu.org/ml/gcc-cvs/2011-07/msg01132.html

I.e. r176864, applied to the 4.6 branch.

Still, at r176866, g++.dg/tree-ssa/fwprop-align.C fails on trunk for cris-elf.
(For which the test never failed on the 4.6 branch.)

For cris-elf, code has to be 16-bit-aligned but otherwise there are no
alignment restrictions.  Perhaps that's related to the failure.

[Bug middle-end/49545] [4.6 Regression] New C++ test failures

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49545

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED

--- Comment #14 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-08-01 14:39:16 UTC ---
Fixed.  The cris issue seems to be sth else.

[Bug middle-end/49545] [4.6 Regression] New C++ test failures

[hp at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49545

--- Comment #15 from Hans-Peter Nilsson <hp at gcc dot gnu.org> 2011-08-01 20:16:28 UTC ---
(In reply to comment #14)
> Fixed.  The cris issue seems to be sth else.

Whatever, as long as it helps fixing the bug. Cloning this PR then.