[Bug c/64032] New: FAIL: gcc.dg/undefined-loop-2.c (test for warnings, line 18)

[Bug c/64032] New: FAIL: gcc.dg/undefined-loop-2.c (test for warnings, line 18)

[danglin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64032

            Bug ID: 64032
           Summary: FAIL: gcc.dg/undefined-loop-2.c  (test for warnings,
                    line 18)
           Product: gcc
           Version: 5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: danglin at gcc dot gnu.org
              Host: hppa-unknown-linux-gnu
            Target: hppa-unknown-linux-gnu
             Build: hppa-unknown-linux-gnu

Executing on host: /home/dave/gnu/gcc/objdir/gcc/xgcc
-B/home/dave/gnu/gcc/objdi
r/gcc/ /home/dave/gnu/gcc/gcc/gcc/testsuite/gcc.dg/undefined-loop-2.c 
-fno-diag
nostics-show-caret -fdiagnostics-color=never   -O2
-Waggressive-loop-optimizatio
ns -S   -o undefined-loop-2.s    (timeout = 300)
spawn /home/dave/gnu/gcc/objdir/gcc/xgcc -B/home/dave/gnu/gcc/objdir/gcc/
/home/
dave/gnu/gcc/gcc/gcc/testsuite/gcc.dg/undefined-loop-2.c
-fno-diagnostics-show-c
aret -fdiagnostics-color=never -O2 -Waggressive-loop-optimizations -S -o
undefin
ed-loop-2.s
/home/dave/gnu/gcc/gcc/gcc/testsuite/gcc.dg/undefined-loop-2.c: In function
'foo
':
/home/dave/gnu/gcc/gcc/gcc/testsuite/gcc.dg/undefined-loop-2.c:19:8: warning:
lo
op exit may only be reached after undefined behavior
[-Waggressive-loop-optimiza
tions]
/home/dave/gnu/gcc/gcc/gcc/testsuite/gcc.dg/undefined-loop-2.c:17:17: note:
poss
ible undefined statement is here
/home/dave/gnu/gcc/gcc/gcc/testsuite/gcc.dg/undefined-loop-2.c:16:17: note:
poss
ible undefined statement is here
output is:
/home/dave/gnu/gcc/gcc/gcc/testsuite/gcc.dg/undefined-loop-2.c: In function
'foo
':
/home/dave/gnu/gcc/gcc/gcc/testsuite/gcc.dg/undefined-loop-2.c:19:8: warning:
lo
op exit may only be reached after undefined behavior
[-Waggressive-loop-optimiza
tions]
/home/dave/gnu/gcc/gcc/gcc/testsuite/gcc.dg/undefined-loop-2.c:17:17: note:
possible undefined statement is here
/home/dave/gnu/gcc/gcc/gcc/testsuite/gcc.dg/undefined-loop-2.c:16:17: note:
possible undefined statement is here

PASS: gcc.dg/undefined-loop-2.c  (test for warnings, line 16)
PASS: gcc.dg/undefined-loop-2.c  (test for warnings, line 17)
FAIL: gcc.dg/undefined-loop-2.c  (test for warnings, line 18)
PASS: gcc.dg/undefined-loop-2.c  (test for warnings, line 19)
PASS: gcc.dg/undefined-loop-2.c (test for excess errors)

[Bug middle-end/64032] [5 Regression] FAIL: gcc.dg/undefined-loop-2.c (test for warnings, line 18)

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64032

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Target|hppa-unknown-linux-gnu      |hppa-unknown-linux-gnu,
                   |                            |i?86-*-*
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2014-11-24
          Component|c                           |middle-end
                 CC|                            |ams at gcc dot gnu.org
     Ever confirmed|0                           |1
            Summary|FAIL:                       |[5 Regression] FAIL:
                   |gcc.dg/undefined-loop-2.c   |gcc.dg/undefined-loop-2.c
                   |(test for warnings, line    |(test for warnings, line
                   |18)                         |18)
   Target Milestone|---                         |5.0

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
I also see this on x86_64 with -m32.

[Bug testsuite/64032] [5 Regression] FAIL: gcc.dg/undefined-loop-2.c (test for warnings, line 18)

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64032

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P1
          Component|middle-end                  |testsuite

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
fold has always done this kind of stuff.

[Bug testsuite/64032] [5 Regression] FAIL: gcc.dg/undefined-loop-2.c (test for warnings, line 18)

[belagod at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64032

Tejas Belagod <belagod at gcc dot gnu.org> changed:

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

--- Comment #4 from Tejas Belagod <belagod at gcc dot gnu.org> ---
Also fails on aarch64.

$ aarch64-none-elf-gcc -O2 -Waggressive-loop-optimizations -S
/work/dev/arm/src/gcc/gcc/testsuite/gcc.dg/undefined-loop-2.c
/work/dev/arm/src/gcc/gcc/testsuite/gcc.dg/undefined-loop-2.c: In function
'foo':
/work/dev/arm/src/gcc/gcc/testsuite/gcc.dg/undefined-loop-2.c:19:8: warning:
loop exit may only be reached after undefined behavior
[-Waggressive-loop-optimizations]
        && i < 100;   /* { dg-warning "loop exit may only be reached after
undefined behavior" } */
        ^
/work/dev/arm/src/gcc/gcc/testsuite/gcc.dg/undefined-loop-2.c:17:17: note:
possible undefined statement is here
         : array2[i]) /* { dg-message "note: possible undefined statement is
here" } */
                 ^
/work/dev/arm/src/gcc/gcc/testsuite/gcc.dg/undefined-loop-2.c:16:17: note:
possible undefined statement is here
         ? array1[i]  /* { dg-message "note: possible undefined statement is
here" } */

[Bug testsuite/64032] [5 Regression] FAIL: gcc.dg/undefined-loop-2.c (test for warnings, line 18)

[ams at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64032

--- Comment #5 from Andrew Stubbs <ams at gcc dot gnu.org> ---
Author: ams
Date: Wed Dec 24 14:27:06 2014
New Revision: 219059

URL: https://gcc.gnu.org/viewcvs?rev=219059&root=gcc&view=rev
Log:
Fix undefined-loop-2.c test case.

2014-12-24  Andrew Stubbs  <ams@codesourcery.com>

    PR testsuite/64032
    * gcc.dg/undefined-loop-2.c: Don't allow GCC to optimize away the
    loop exits too early.

Modified:
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gcc.dg/undefined-loop-2.c

[Bug testsuite/64032] [5 Regression] FAIL: gcc.dg/undefined-loop-2.c (test for warnings, line 18)

[ams at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64032

Andrew Stubbs <ams at gcc dot gnu.org> changed:

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

--- Comment #6 from Andrew Stubbs <ams at gcc dot gnu.org> ---
I've just committed a patch to fix this. It works on x86_64, ARM, and PowerPC,
at least.