[Bug other/115140] New: [15 regression] libgomp.oacc-c++/../libgomp.oacc-c-c++-common/acc_prof-kernels-1.c excess errors after r15-579-ga9251ab3c91c8c

[Bug other/115140] New: [15 regression] libgomp.oacc-c++/../libgomp.oacc-c-c++-common/acc_prof-kernels-1.c excess errors after r15-579-ga9251ab3c91c8c

[seurer at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115140

            Bug ID: 115140
           Summary: [15 regression]
                    libgomp.oacc-c++/../libgomp.oacc-c-c++-common/acc_prof
                    -kernels-1.c excess errors after
                    r15-579-ga9251ab3c91c8c
           Product: gcc
           Version: 15.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: other
          Assignee: unassigned at gcc dot gnu.org
          Reporter: seurer at gcc dot gnu.org
  Target Milestone: ---

g:a9251ab3c91c8c559d0306838575a666ae62dff4, r15-579-ga9251ab3c91c8c: 1130
failures

FAIL: libgomp.oacc-c++/../libgomp.oacc-c-c++-common/acc_prof-kernels-1.c
-DACC_DEVICE_TYPE_host=1 -DACC_MEM_SHARED=1 -foffload=disable  -O2   at line
190 (test for warnings, line 185)
FAIL: libgomp.oacc-c++/../libgomp.oacc-c-c++-common/acc_prof-kernels-1.c
-DACC_DEVICE_TYPE_host=1 -DACC_MEM_SHARED=1 -foffload=disable  -O2   at line
221 (test for warnings, line 214)
FAIL: libgomp.oacc-c++/../libgomp.oacc-c-c++-common/acc_prof-kernels-1.c
-DACC_DEVICE_TYPE_host=1 -DACC_MEM_SHARED=1 -foffload=disable  -O2   at line
252 (test for warnings, line 245)
FAIL: libgomp.oacc-c++/../libgomp.oacc-c-c++-common/acc_prof-kernels-1.c
-DACC_DEVICE_TYPE_host=1 -DACC_MEM_SHARED=1 -foffload=disable  -O2  (test for
excess errors)
FAIL: libgomp.oacc-c/../libgomp.oacc-c-c++-common/acc_prof-kernels-1.c
-DACC_DEVICE_TYPE_host=1 -DACC_MEM_SHARED=1 -foffload=disable  -O2   at line
190 (test for warnings, line 185)
FAIL: libgomp.oacc-c/../libgomp.oacc-c-c++-common/acc_prof-kernels-1.c
-DACC_DEVICE_TYPE_host=1 -DACC_MEM_SHARED=1 -foffload=disable  -O2   at line
221 (test for warnings, line 214)
FAIL: libgomp.oacc-c/../libgomp.oacc-c-c++-common/acc_prof-kernels-1.c
-DACC_DEVICE_TYPE_host=1 -DACC_MEM_SHARED=1 -foffload=disable  -O2   at line
252 (test for warnings, line 245)
FAIL: libgomp.oacc-c/../libgomp.oacc-c-c++-common/acc_prof-kernels-1.c
-DACC_DEVICE_TYPE_host=1 -DACC_MEM_SHARED=1 -foffload=disable  -O2  (test for
excess errors)

commit a9251ab3c91c8c559d0306838575a666ae62dff4 (HEAD)
Author: Richard Biener <rguenther@suse.de>
Date:   Thu May 16 12:35:28 2024 +0200

    wrong code with points-to and volatile



Excess errors:
/home/seurer/gcc/git/gcc-test2/libgomp/testsuite/libgomp.oacc-c/../libgomp.oacc-c-c++-common/acc_prof-kernels-1.c:185:9:
optimized: assigned OpenACC seq loop parallelism
/home/seurer/gcc/git/gcc-test2/libgomp/testsuite/libgomp.oacc-c/../libgomp.oacc-c-c++-common/acc_prof-kernels-1.c:214:9:
optimized: assigned OpenACC seq loop parallelism
/home/seurer/gcc/git/gcc-test2/libgomp/testsuite/libgomp.oacc-c/../libgomp.oacc-c-c++-common/acc_prof-kernels-1.c:245:9:
optimized: assigned OpenACC seq loop parallelism

[Bug other/115140] [15 regression] libgomp.oacc-c++/../libgomp.oacc-c-c++-common/acc_prof-kernels-1.c excess errors after r15-579-ga9251ab3c91c8c

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115140

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |15.0

[Bug testsuite/115140] [15 regression] libgomp.oacc-c++/../libgomp.oacc-c-c++-common/acc_prof-kernels-1.c excess errors after r15-579-ga9251ab3c91c8c

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115140

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|other                       |testsuite
           Keywords|                            |openacc

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
Looks like a testsuite artifact?

volatile // TODO PR90488
static int state = -1;

I've not looked as to why/how we are getting that to influence points-to
solutions (note as we track also integers volatile on non-pointers can
matter).

[Bug testsuite/115140] [15 regression] libgomp.oacc-c++/../libgomp.oacc-c-c++-common/acc_prof-kernels-1.c excess errors after r15-579-ga9251ab3c91c8c

[ro at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115140

Rainer Orth <ro at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
               Host|powerpc64-linux-gnu,        |powerpc64-linux-gnu,
                   |powerpc64le-linux-gnu       |powerpc64le-linux-gnu,
                   |                            |*-*-solaris2.11
                 CC|                            |ro at gcc dot gnu.org
              Build|powerpc64-linux-gnu,        |powerpc64-linux-gnu,
                   |powerpc64le-linux-gnu       |powerpc64le-linux-gnu,
                   |                            |*-*-solaris2.11
             Target|powerpc64-linux-gnu,        |powerpc64-linux-gnu,
                   |powerpc64le-linux-gnu       |powerpc64le-linux-gnu,
                   |                            |*-*-solaris2.11

--- Comment #2 from Rainer Orth <ro at gcc dot gnu.org> ---
Also seen on Solaris/SPARC and x86.

[Bug testsuite/115140] [15 regression] libgomp.oacc-c++/../libgomp.oacc-c-c++-common/acc_prof-kernels-1.c excess errors after r15-579-ga9251ab3c91c8c

[tschwinge at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115140

Thomas Schwinge <tschwinge at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
               Host|powerpc64-linux-gnu,        |
                   |powerpc64le-linux-gnu,      |
                   |*-*-solaris2.11             |
              Build|powerpc64-linux-gnu,        |
                   |powerpc64le-linux-gnu,      |
                   |*-*-solaris2.11             |
                 CC|                            |tschwinge at gcc dot gnu.org
             Status|UNCONFIRMED                 |NEW
             Target|powerpc64-linux-gnu,        |
                   |powerpc64le-linux-gnu,      |
                   |*-*-solaris2.11             |
   Last reconfirmed|                            |2024-05-24
     Ever confirmed|0                           |1

--- Comment #3 from Thomas Schwinge <tschwinge at gcc dot gnu.org> ---
So the PASS -> FAIL regressions are due to parloops (for '-O2') no longer
parallelizing the simple OpenACC 'kernels' construct at line 185 (and two
more):

    int x[N];
    #pragma acc kernels
    {
      for (int i = 0; i < N; ++i)
        x[i] = i * i;
    }

(In reply to Richard Biener from comment #1)
> Looks like a testsuite artifact?
> 
> volatile // TODO PR90488
> static int state = -1;
> 
> I've not looked as to why/how we are getting that to influence points-to
> solutions (note as we track also integers volatile on non-pointers can
> matter).

Yeah, it's not obvious to me how that 'state' variable would have such an
effect -- but I've not yet 'diff'ed the dumps.

On the other hand, it's highly likely that there is some relation, as no other
OpenACC 'kernels' test cases did regress.