[Bug c/47002] New: segmentation fault in find_uses_to_rename_use

[Bug c/47002] New: segmentation fault in find_uses_to_rename_use

[dcb314 at hotmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47002

           Summary: segmentation fault in find_uses_to_rename_use
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: dcb314@hotmail.com


Created attachment 22809
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=22809
C source code

I just tried to compile package covered-0.7.7 with the latest 4.6
snapshot 20101211 on a Fedora Linux box. The compiler said

../src/vector.c: In function 'vector_set_value_ulong':
../src/vector.c:1857:6: 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.

valgrind says

==11010== Invalid read of size 8
==11010==    at 0x8B1809: find_uses_to_rename_use (tree-ssa-loop-manip.c:1246)
==11010==    by 0x8B1A27: find_uses_to_rename_bb (tree-ssa-loop-manip.c:301)
==11010==    by 0x8B216D: rewrite_into_loop_closed_ssa
(tree-ssa-loop-manip.c:331)
==11010==    by 0x82A239: distribute_loop (tree-loop-distribution.c:1020)
==11010==    by 0x82B15C: tree_loop_distribution
(tree-loop-distribution.c:1146)
==11010==    by 0x74510E: execute_one_pass (passes.c:1553)
==11010==    by 0x7453B4: execute_pass_list (passes.c:1608)
==11010==    by 0x7453C6: execute_pass_list (passes.c:1609)
==11010==    by 0x7453C6: execute_pass_list (passes.c:1609)
==11010==    by 0x838CD5: tree_rest_of_compilation (tree-optimize.c:422)
==11010==    by 0x9D6540: cgraph_expand_function (cgraphunit.c:1508)
==11010==    by 0x9D8AA9: cgraph_optimize (cgraphunit.c:1567)
==11010==  Address 0x10 is not stack'd, malloc'd or (recently) free'd
==11010==

Source code attached. Flag -O3 required.

[Bug c/47002] [4.6 Regression] segmentation fault in find_uses_to_rename_use

[hjl.tools at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47002

H.J. Lu <hjl.tools at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2010.12.18 14:26:06
                 CC|                            |spop at gcc dot gnu.org
   Target Milestone|---                         |4.6.0
            Summary|segmentation fault in       |[4.6 Regression]
                   |find_uses_to_rename_use     |segmentation fault in
                   |                            |find_uses_to_rename_use
     Ever Confirmed|0                           |1

--- Comment #1 from H.J. Lu <hjl.tools at gmail dot com> 2010-12-18 14:26:06 UTC ---
It is caused by revision 162822:

http://gcc.gnu.org/ml/gcc-cvs/2010-08/msg00033.html

[Bug tree-optimization/47002] [4.6 Regression] segmentation fault in find_uses_to_rename_use

[spop at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47002

--- Comment #2 from Sebastian Pop <spop at gcc dot gnu.org> 2010-12-20 05:23:29 UTC ---
I cannot reproduce the error on amd64-linux with "./cc1 -O3 bug.i"
Please report the exact flags and the architecture.

However I can see several unrelated memory leaks (i.e., not the one reported)
with 
valgrind --leak-check=full ./cc1 -O3 bug.i

[Bug tree-optimization/47002] [4.6 Regression] segmentation fault in find_uses_to_rename_use

[spop at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47002

--- Comment #3 from Sebastian Pop <spop at gcc dot gnu.org> 2010-12-20 05:25:00 UTC ---
I tested trunk@168000.

[Bug tree-optimization/47002] [4.6 Regression] segmentation fault in find_uses_to_rename_use

[spop at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47002

Sebastian Pop <spop at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |WAITING

--- Comment #4 from Sebastian Pop <spop at gcc dot gnu.org> 2010-12-22 06:23:54 UTC ---
Patch fixing the memory leaks related to loop distribution:
http://gcc.gnu.org/ml/gcc-patches/2010-12/msg01670.html

I still cannot reproduce the error reported in this PR.
HJ, it seems like you were able to see the ICE.
Could you please specify which flags and architecture you used?
Thanks.

[Bug tree-optimization/47002] [4.6 Regression] segmentation fault in find_uses_to_rename_use

[spop at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47002

--- Comment #5 from Sebastian Pop <spop at gcc dot gnu.org> 2010-12-23 16:25:59 UTC ---
Author: spop
Date: Thu Dec 23 16:25:52 2010
New Revision: 168210

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=168210
Log:
Fix PR47002: memory leaks.

2010-12-23  Sebastian Pop  <sebastian.pop@amd.com>

    PR tree-optimization/47002
    * tree-data-ref.c (compute_data_dependences_for_loop): Pass in a
    pointer to the loop_nest.
    (analyze_all_data_dependences): Initialize and free the loop_nest.
    (free_dependence_relations): Do not free loop_nest.
    (build_rdg): Pass in the loop_nest, datarefs, and dependence_relations.
    (free_rdg): Also free the data on edges.
    * tree-data-ref.h (build_rdg): Update declaration.
    (compute_data_dependences_for_loop): Same.
    * tree-if-conv.c (if_convertible_loop_p_1): Pass in the loop_nest.
    (if_convertible_loop_p): Allocate and free loop_nest.
    * tree-loop-distribution.c (rdg_flag_loop_exits): Free conds.
    (free_rdg_components): VEC_free components.
    (distribute_loop): Update call to build_rdg.  Allocate and free
    loop_nest, datarefs, and dependence_relations.
    * tree-loop-linear.c (linear_transform_loops): Allocate and free
    loop_nest.
    * tree-parloops.c (loop_parallel_p): Same.
    * tree-predcom.c (tree_predictive_commoning_loop): Same.
    * tree-vect-data-refs.c (vect_analyze_data_refs): Pass to
    compute_data_dependences_for_loop a pointer to LOOP_VINFO_LOOP_NEST.
    * tree-vect-loop.c (new_loop_vec_info): Initialize LOOP_VINFO_LOOP_NEST.
    (destroy_loop_vec_info): Free LOOP_VINFO_MAY_ALIAS_DDRS and
    LOOP_VINFO_LOOP_NEST.
    * tree-vect-slp.c (destroy_bb_vec_info): Call free_data_refs and
    free_dependence_relations.
    * tree-vectorizer.h (struct _loop_vec_info): Add a field loop_nest.
    (LOOP_VINFO_LOOP_NEST): New.

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/tree-data-ref.c
    trunk/gcc/tree-data-ref.h
    trunk/gcc/tree-if-conv.c
    trunk/gcc/tree-loop-distribution.c
    trunk/gcc/tree-loop-linear.c
    trunk/gcc/tree-parloops.c
    trunk/gcc/tree-predcom.c
    trunk/gcc/tree-vect-data-refs.c
    trunk/gcc/tree-vect-loop.c
    trunk/gcc/tree-vect-slp.c
    trunk/gcc/tree-vectorizer.h

[Bug tree-optimization/47002] [4.6 Regression] segmentation fault in find_uses_to_rename_use

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47002

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

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

--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> 2010-12-31 11:18:55 UTC ---
Can't reproduce with neither 20101217 trunk nor current trunk on x86_64-linux
either, can the reporter and/or hjl double check current trunk?
Thanks.

[Bug tree-optimization/47002] [4.6 Regression] segmentation fault in find_uses_to_rename_use

[dcb314 at hotmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47002

--- Comment #7 from dcb <dcb314 at hotmail dot com> 2010-12-31 12:43:27 UTC ---
(In reply to comment #6)
> Can't reproduce with neither 20101217 trunk nor current trunk on x86_64-linux
> either, can the reporter and/or hjl double check current trunk?
> Thanks.

I rechecked, and the problem seems to have gone away as of 
snapshot 20101225.

I am not quite clear if SP's patch is for the memory leaks
only or has fixed the original problem as well.

[Bug tree-optimization/47002] [4.6 Regression] segmentation fault in find_uses_to_rename_use

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47002

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

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

--- Comment #8 from Jakub Jelinek <jakub at gcc dot gnu.org> 2010-12-31 14:13:02 UTC ---
Assuming it is fixed then.