[Bug middle-end/46034] New: internal compiler error: Segmentation fault

[Bug middle-end/46034] New: internal compiler error: Segmentation fault

[moonshine at kapsi dot fi]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46034

           Summary: internal compiler error: Segmentation fault
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: moonshine@kapsi.fi


Created attachment 22052
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=22052
a reduced testcase

This is a delta-reduced testcase, original has no warnings.

$ gcc-trunk -c -O2 tc.i
tc.i:208:1: warning: data definition has no type or storage class [enabled by
default]
tc.i:296:5: warning: data definition has no type or storage class [enabled by
default]
tc.i:441:5: warning: data definition has no type or storage class [enabled by
default]
tc.i:465:1: warning: data definition has no type or storage class [enabled by
default]
tc.i:539:1: warning: data definition has no type or storage class [enabled by
default]
tc.i:541:1: warning: data definition has no type or storage class [enabled by
default]
tc.i:543:1: warning: data definition has no type or storage class [enabled by
default]
tc.i:545:1: warning: data definition has no type or storage class [enabled by
default]
tc.i:680:3: warning: data definition has no type or storage class [enabled by
default]
tc.i: In function ‘add_y_curve_part’:
tc.i:837:24: warning: initialization makes pointer from integer without a cast
[enabled by default]
tc.i: In function ‘add_y_line_aux’:
tc.i:925:24: warning: initialization makes pointer from integer without a cast
[enabled by default]
gcc-trunk: internal compiler error: Segmentation fault (program cc1)
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.

[Bug middle-end/46034] internal compiler error: Segmentation fault

[moonshine at kapsi dot fi]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46034

--- Comment #1 from Juhani Viheräkoski <moonshine at kapsi dot fi> 2010-10-15 12:10:28 UTC ---
$ gcc-trunk -v
Using built-in specs.
COLLECT_GCC=gcc-trunk
COLLECT_LTO_WRAPPER=/home/misty/gcc/libexec/gcc/i686-pc-linux-gnu/4.6.0/lto-wrapper
Target: i686-pc-linux-gnu
Configured with: ../gcc-trunk/configure --prefix=/home/misty/gcc
--enable-languages=c,c++ --enable-gold --enable-lto --enable-plugins
--program-suffix=-trunk --enable-checking=yes --disable-stage1-checking
Thread model: posix
gcc version 4.6.0 20101014 (experimental) (GCC) 

Revision: 165459

[Bug middle-end/46034] [4.6 regression] internal compiler error: Segmentation fault

[moonshine at kapsi dot fi]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46034

Juhani Viheräkoski <moonshine at kapsi dot fi> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|internal compiler error:    |[4.6 regression] internal
                   |Segmentation fault          |compiler error:
                   |                            |Segmentation fault

--- Comment #2 from Juhani Viheräkoski <moonshine at kapsi dot fi> 2010-10-15 15:27:10 UTC ---
Compiles with latest 4.5 svn so this is a regression.

[Bug rtl-optimization/46034] [4.6 regression] internal compiler error: Segmentation fault

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46034

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |ice-on-valid-code
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2010.10.27 22:14:25
          Component|middle-end                  |rtl-optimization
     Ever Confirmed|0                           |1

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> 2010-10-27 22:14:25 UTC ---
#0  if_then_else_cond (x=0x7f4d072f7b10, ptrue=0x7fff4c5ea078,
pfalse=0x7fff4c5ea068)
    at /home/apinski/src/gcc-fsf/local//gcc/gcc/combine.c:8468


Confirmed.

[Bug rtl-optimization/46034] [4.6 regression] internal compiler error: Segmentation fault

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46034

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |4.6.0

[Bug rtl-optimization/46034] [4.6 regression] internal compiler error: Segmentation fault

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46034

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> 2010-10-27 22:16:55 UTC ---
We are going into an infinite loop in  if_then_else_cond.

[Bug rtl-optimization/46034] [4.6 regression] internal compiler error: Segmentation fault

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46034

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> 2010-10-27 22:19:13 UTC ---
But that is because we have something like XOR (ASHIFTRT) Where the operand of
the ASHIFTRT is the same XOR again.

[Bug rtl-optimization/46034] [4.6 regression] internal compiler error: Segmentation fault

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46034

--- Comment #6 from Andrew Pinski <pinskia at gcc dot gnu.org> 2010-10-27 22:34:40 UTC ---
The most reduced testcase I could get:
intersect_al(int n, int k)
{
  int i;
  for (i = 0; i < n; i++)
  {
    k = __builtin_abs(k);
    set_x_next(k / 2);
  }
}

[Bug rtl-optimization/46034] [4.6 regression] internal compiler error: Segmentation fault

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46034

--- Comment #7 from Andrew Pinski <pinskia at gcc dot gnu.org> 2010-10-27 22:38:26 UTC ---
Fails also with revision 164656.

[Bug rtl-optimization/46034] [4.6 regression] internal compiler error: Segmentation fault

[zsojka at seznam dot cz]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46034

--- Comment #8 from Zdenek Sojka <zsojka at seznam dot cz> 2010-10-27 22:59:53 UTC ---
Created attachment 22186
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=22186
reduced testcase

Needs only "-O -fexpensive-optimizations" to reproduce

Relevant valgrind output:
$ gcc -O -fexpensive-optimizations testcase2.c
==10818== 
==10818== Stack overflow in thread 1: can't grow stack to 0x7fe801fd8
==10818== Can't extend stack to 0x7fe801450 during signal delivery for thread
1:
==10818==   no stack segment
==10818== 
==10818== Process terminating with default action of signal 11 (SIGSEGV)
==10818==  Access not within mapped region at address 0x7FE801450
==10818==    at 0xF1C9BB: if_then_else_cond (combine.c:8504)
==10818==  If you believe this happened as a result of a stack
==10818==  overflow in your program's main thread (unlikely but
==10818==  possible), you can try to increase the size of the
==10818==  main thread stack using the --main-stacksize= flag.
==10818==  The main thread stack size used in this run was 8388608.
==10818== Stack overflow in thread 1: can't grow stack to 0x7fe801f50
gcc: internal compiler error: Segmentation fault (program cc1)
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.

Tested revisions:
r165985 - crash
r163636 - crash
r161659 - OK

[Bug rtl-optimization/46034] [4.6 regression] internal compiler error: Segmentation fault

[ebotcazou at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46034

Eric Botcazou <ebotcazou at gcc dot gnu.org> changed:

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

--- Comment #9 from Eric Botcazou <ebotcazou at gcc dot gnu.org> 2010-10-28 10:34:35 UTC ---
Investigating.

[Bug rtl-optimization/46034] [4.6 regression] internal compiler error: Segmentation fault

[hjl.tools at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46034

--- Comment #10 from H.J. Lu <hjl.tools at gmail dot com> 2010-10-28 16:05:44 UTC ---
It is caused by revision 163383:

http://gcc.gnu.org/ml/gcc-cvs/2010-08/msg00595.html

[Bug rtl-optimization/46034] [4.6 regression] internal compiler error: segmentation fault

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46034

--- Comment #11 from Jakub Jelinek <jakub at gcc dot gnu.org> 2010-11-01 11:25:04 UTC ---
Created attachment 22218
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=22218
gcc46-pr46034.patch

Untested fix.

[Bug rtl-optimization/46034] [4.6 regression] internal compiler error: segmentation fault

[ebotcazou at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46034

Eric Botcazou <ebotcazou at gcc dot gnu.org> changed:

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

[Bug rtl-optimization/46034] [4.6 regression] internal compiler error: segmentation fault

[moonshine at kapsi dot fi]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46034

Juhani Viheräkoski <moonshine at kapsi dot fi> changed:

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

--- Comment #12 from Juhani Viheräkoski <moonshine at kapsi dot fi> 2010-11-03 00:28:06 UTC ---
Tested with original testcase extracted from Ghostscript, passes on
i686-linux-gnu with the proposed patch.

[Bug rtl-optimization/46034] [4.6 regression] internal compiler error: segmentation fault

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46034

--- Comment #13 from Jakub Jelinek <jakub at gcc dot gnu.org> 2010-11-03 08:30:30 UTC ---
Author: jakub
Date: Wed Nov  3 08:30:21 2010
New Revision: 166231

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=166231
Log:
    PR rtl-optimization/46034
    PR rtl-optimization/46212
    PR rtl-optimization/46248
    * combine.c (try_combine): If added_sets_2 where i0dest_in_i0src
    and i0 feeds i1 and i1 feeds i2 or i0 feeds i2, make a copy of i1src
    before i0dest -> i0src substitution and pass 1 instead of 0 as last
    argument to subst on i2pat.

    * gcc.c-torture/compile/pr46034.c: New test.
    * gcc.c-torture/compile/pr46248.c: New test.
    * gcc.dg/pr46212.c: New test.

Added:
    trunk/gcc/testsuite/gcc.c-torture/compile/pr46034.c
    trunk/gcc/testsuite/gcc.c-torture/compile/pr46248.c
    trunk/gcc/testsuite/gcc.dg/pr46212.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/combine.c
    trunk/gcc/testsuite/ChangeLog