[Bug c/53580] New: Internal Segmentation fault in nested "omp parallel", "omp parallel for" and "omp parallel for reduction" Directives

[Bug c/53580] New: Internal Segmentation fault in nested "omp parallel", "omp parallel for" and "omp parallel for reduction" Directives

[fedediazceo at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53580

             Bug #: 53580
           Summary: Internal Segmentation fault in nested "omp parallel",
                    "omp parallel for" and "omp parallel for reduction"
                    Directives
    Classification: Unclassified
           Product: gcc
           Version: 4.6.3
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: fedediazceo@gmail.com


Created attachment 27559
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=27559
Attached preprocesses source that the output demands

When trying to compile nested #pragma omp parallel, #pragma omp parallel for
and #pragma omp parallel for reduction (+:variable), the compiler throws an
internal error:segmentation fault.

--------test code------- 

#include <stdio.h>
#include <omp.h>


int main(int argc, char **argv){
    int x, y, variableReduction=0;

    #pragma omp parallel    

    #pragma omp for
    for(x=0; x <= 10 ; x++){
        #pragma omp for reduction(+: variableReduction)
        for(y=0; y <= 10 ; y++){
            variableReduction += 0;
        }
    }
    return variableReduction;
}-----------------------


gcc -v
Using internal specifications.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/4.6/lto-wrapper
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu/Linaro
4.6.3-1ubuntu5' --with-bugurl=file:///usr/share/doc/gcc-4.6/README.Bugs
--enable-languages=c,c++,fortran,objc,obj-c++ --prefix=/usr
--program-suffix=-4.6 --enable-shared --enable-linker-build-id
--with-system-zlib --libexecdir=/usr/lib --without-included-gettext
--enable-threads=posix --with-gxx-include-dir=/usr/include/c++/4.6
--libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu
--enable-libstdcxx-debug --enable-libstdcxx-time=yes --enable-gnu-unique-object
--enable-plugin --enable-objc-gc --disable-werror --with-arch-32=i686
--with-tune=generic --enable-checking=release --build=x86_64-linux-gnu
--host=x86_64-linux-gnu --target=x86_64-linux-gnu
Thread model: posix
gcc version 4.6.3 (Ubuntu/Linaro 4.6.3-1ubuntu5) 

The command line arguments and the output is:

gcc -Wall -Wextra -fopenmp test.c -o test

test.c:12:9: warning: work-sharing region may not be closely nested inside of
work-sharing, critical, ordered, master or explicit task region [enabled by
default]
test.c:12:9: internal compiler error: Segmentation fault
Please submit a full bug report,
with preprocessed source if appropriate.
See <file:///usr/share/doc/gcc-4.6/README.Bugs> for instructions.
Preprocessed source stored into /tmp/cck4oOHH.out file, please attach this to
your bugreport.

Somewhat similar to Bug report 35674
(http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35674) but different compiler
context (i think)

Hope it's clear enough, my first bug report :-)

[Bug c/53580] Internal Segmentation fault in nested "omp parallel", "omp parallel for" and "omp parallel for reduction" Directives

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53580

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

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

--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-06-05 06:34:08 UTC ---
I'll look at it, but note that your testcase is invalid OpenMP.

[Bug c/53580] Internal Segmentation fault in nested "omp parallel", "omp parallel for" and "omp parallel for reduction" Directives

[fernando at info dot unlp.edu.ar]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53580

Fernando G. Tinetti <fernando at info dot unlp.edu.ar> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |fernando at info dot
                   |                            |unlp.edu.ar

--- Comment #2 from Fernando G. Tinetti <fernando at info dot unlp.edu.ar> 2012-06-05 11:07:07 UTC ---
(In reply to comment #1)
> I'll look at it, but note that your testcase is invalid OpenMP.

We saw this with Federico, and we agree in that the testcase is invalid OpenMP
code. Furthermore: 
1) the compiler message is right.
2) should the compiler report an error instead of a warning? (I don't know what
the compiler is required to report...).

Fernando.

[Bug c/53580] Internal Segmentation fault in nested "omp parallel", "omp parallel for" and "omp parallel for reduction" Directives

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53580

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
   Last reconfirmed|                            |2012-06-06
         AssignedTo|unassigned at gcc dot       |jakub at gcc dot gnu.org
                   |gnu.org                     |
     Ever Confirmed|0                           |1

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-06-06 16:05:51 UTC ---
Created attachment 27565
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=27565
gcc48-pr53580.patch

Untested 4.8 patch.

[Bug c/53580] Internal Segmentation fault in nested "omp parallel", "omp parallel for" and "omp parallel for reduction" Directives

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53580

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
  Attachment #27565|0                           |1
        is obsolete|                            |

--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-06-06 17:41:45 UTC ---
Created attachment 27566
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=27566
gcc48-pr53580.patch

Updated 4.8 patch.

[Bug c/53580] Internal Segmentation fault in nested "omp parallel", "omp parallel for" and "omp parallel for reduction" Directives

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53580

--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-06-06 17:50:42 UTC ---
Created attachment 27567
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=27567
gcc47-pr53580.patch

Untested 4.7 patch.

[Bug c/53580] Internal Segmentation fault in nested "omp parallel", "omp parallel for" and "omp parallel for reduction" Directives

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53580

--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-06-07 06:37:00 UTC ---
Author: jakub
Date: Thu Jun  7 06:36:55 2012
New Revision: 188298

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=188298
Log:
    PR middle-end/53580
    * omp-low.c (scan_omp): Change first argument to
    gimple_seq *, call walk_gimple_seq_mod instead of
    walk_gimple_seq.
    (scan_sharing_clauses, scan_omp_parallel, scan_omp_task,
    scan_omp_for, scan_omp_sections, scan_omp_single,
    execute_lower_omp): Adjust callers.
    (scan_omp_1_stmt): Likewise.  If check_omp_nesting_restrictions
    returns false, replace stmt with GIMPLE_NOP.
    (check_omp_nesting_restrictions): Instead of issuing warnings,
    issue errors and return false if any errors were reported.

    * gcc.dg/gomp/nesting-1.c: Expect errors rather than warnings.
    * gcc.dg/gomp/critical-4.c: Likewise.
    * gfortran.dg/gomp/appendix-a/a.35.1.f90: Likewise.
    * gfortran.dg/gomp/appendix-a/a.35.3.f90: Likewise.
    * gfortran.dg/gomp/appendix-a/a.35.4.f90: Likewise.
    * gfortran.dg/gomp/appendix-a/a.35.6.f90: Likewise.
    * c-c++-common/gomp/pr53580.c: New test.

    * testsuite/libgomp.c/pr26943-2.c: Remove #pragma omp barrier,
    use GOMP_barrier () call instead.
    * testsuite/libgomp.c/pr26943-3.c: Likewise.
    * testsuite/libgomp.c/pr26943-4.c: Likewise.
    * testsuite/libgomp.fortran/vla4.f90: Remove !$omp barrier,
    call GOMP_barrier instead.
    * testsuite/libgomp.fortran/vla5.f90: Likewise.

Added:
    trunk/gcc/testsuite/c-c++-common/gomp/pr53580.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/omp-low.c
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gcc.dg/gomp/critical-4.c
    trunk/gcc/testsuite/gcc.dg/gomp/nesting-1.c
    trunk/gcc/testsuite/gfortran.dg/gomp/appendix-a/a.35.1.f90
    trunk/gcc/testsuite/gfortran.dg/gomp/appendix-a/a.35.3.f90
    trunk/gcc/testsuite/gfortran.dg/gomp/appendix-a/a.35.4.f90
    trunk/gcc/testsuite/gfortran.dg/gomp/appendix-a/a.35.6.f90
    trunk/libgomp/ChangeLog
    trunk/libgomp/testsuite/libgomp.c/pr26943-2.c
    trunk/libgomp/testsuite/libgomp.c/pr26943-3.c
    trunk/libgomp/testsuite/libgomp.c/pr26943-4.c
    trunk/libgomp/testsuite/libgomp.fortran/vla4.f90
    trunk/libgomp/testsuite/libgomp.fortran/vla5.f90

[Bug c/53580] Internal Segmentation fault in nested "omp parallel", "omp parallel for" and "omp parallel for reduction" Directives

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53580

--- Comment #7 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-06-14 17:48:42 UTC ---
Author: jakub
Date: Thu Jun 14 17:48:38 2012
New Revision: 188625

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=188625
Log:
    Backported from mainline
    2012-06-07  Jakub Jelinek  <jakub@redhat.com>

    PR middle-end/53580
    * omp-low.c (scan_omp_1_stmt): If check_omp_nesting_restrictions
    returns false, replace stmt with GIMPLE_NOP.
    (check_omp_nesting_restrictions): Instead of issuing warnings,
    issue errors and return false if any errors were reported.

    * gcc.dg/gomp/nesting-1.c: Expect errors rather than warnings.
    * gcc.dg/gomp/critical-4.c: Likewise.
    * gfortran.dg/gomp/appendix-a/a.35.1.f90: Likewise.
    * gfortran.dg/gomp/appendix-a/a.35.3.f90: Likewise.
    * gfortran.dg/gomp/appendix-a/a.35.4.f90: Likewise.
    * gfortran.dg/gomp/appendix-a/a.35.6.f90: Likewise.
    * c-c++-common/gomp/pr53580.c: New test.

    * testsuite/libgomp.c/pr26943-2.c: Remove #pragma omp barrier,
    use GOMP_barrier () call instead.
    * testsuite/libgomp.c/pr26943-3.c: Likewise.
    * testsuite/libgomp.c/pr26943-4.c: Likewise.
    * testsuite/libgomp.fortran/vla4.f90: Remove !$omp barrier,
    call GOMP_barrier instead.
    * testsuite/libgomp.fortran/vla5.f90: Likewise.

Added:
    branches/gcc-4_7-branch/gcc/testsuite/c-c++-common/gomp/pr53580.c
Modified:
    branches/gcc-4_7-branch/gcc/ChangeLog
    branches/gcc-4_7-branch/gcc/omp-low.c
    branches/gcc-4_7-branch/gcc/testsuite/ChangeLog
    branches/gcc-4_7-branch/gcc/testsuite/gcc.dg/gomp/critical-4.c
    branches/gcc-4_7-branch/gcc/testsuite/gcc.dg/gomp/nesting-1.c
   
branches/gcc-4_7-branch/gcc/testsuite/gfortran.dg/gomp/appendix-a/a.35.1.f90
   
branches/gcc-4_7-branch/gcc/testsuite/gfortran.dg/gomp/appendix-a/a.35.3.f90
   
branches/gcc-4_7-branch/gcc/testsuite/gfortran.dg/gomp/appendix-a/a.35.4.f90
   
branches/gcc-4_7-branch/gcc/testsuite/gfortran.dg/gomp/appendix-a/a.35.6.f90
    branches/gcc-4_7-branch/libgomp/ChangeLog
    branches/gcc-4_7-branch/libgomp/testsuite/libgomp.c/pr26943-2.c
    branches/gcc-4_7-branch/libgomp/testsuite/libgomp.c/pr26943-3.c
    branches/gcc-4_7-branch/libgomp/testsuite/libgomp.c/pr26943-4.c
    branches/gcc-4_7-branch/libgomp/testsuite/libgomp.fortran/vla4.f90
    branches/gcc-4_7-branch/libgomp/testsuite/libgomp.fortran/vla5.f90

[Bug c/53580] Internal Segmentation fault in nested "omp parallel", "omp parallel for" and "omp parallel for reduction" Directives

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53580

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

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

--- Comment #8 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-06-15 11:12:27 UTC ---
FIxed for 4.7+, not backporting further, as this is ice-on-invalid only.