[Bug other/53284] New: Several libatomic tests fail on 32-bit Solaris/x86

[Bug other/53284] New: Several libatomic tests fail on 32-bit Solaris/x86

[ro at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53284

             Bug #: 53284
           Summary: Several libatomic tests fail on 32-bit Solaris/x86
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: other
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: ro@gcc.gnu.org
                CC: rth@gcc.gnu.org
              Host: i386-pc-solaris2.9, i386-pc-solaris2.1[01]
            Target: i386-pc-solaris2.9, i386-pc-solaris2.1[01]
             Build: i386-pc-solaris2.9, i386-pc-solaris2.1[01]


With the libatomic build problems on Solaris out of the way, there remain a
couple
of testsuite failures for the default 32-bit multilib:

FAIL: libatomic.c/atomic-compare-exchange-4.c execution test
FAIL: libatomic.c/atomic-exchange-4.c execution test
FAIL: libatomic.c/atomic-load-4.c execution test
FAIL: libatomic.c/atomic-op-4.c execution test
FAIL: libatomic.c/atomic-store-4.c execution test
FAIL: libatomic.c/generic-2.c execution test

It seems all of them SEGV, e.g.

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 1 (LWP 1)]
0xfef823f7 in libat_compare_exchange_8 (mptr=0x8049e68, eptr=0x8049e70,
newval=18446744073709551615, smodel=5, fmodel=0) at
/vol/gcc/src/hg/trunk/local/libatomic/cas_n.c:41
(gdb) where
#0  0xfef823f7 in libat_compare_exchange_8 (mptr=0x8049e68, eptr=0x8049e70,
newval=18446744073709551615, smodel=5, fmodel=0) at
/vol/gcc/src/hg/trunk/local/libatomic/cas_n.c:41
#1  0xfef823fc in libat_compare_exchange_8 (mptr=0x8049e68, eptr=0x8049e70,
newval=18446744073709551615, smodel=5, fmodel=0) at
/vol/gcc/src/hg/trunk/local/libatomic/cas_n.c:41
#2  0xfef823fc in libat_compare_exchange_8 (mptr=0x8049e68, eptr=0x8049e70,
newval=18446744073709551615, smodel=5, fmodel=0) at
/vol/gcc/src/hg/trunk/local/libatomic/cas_n.c:41
#3  0xfef823fc in libat_compare_exchange_8 (mptr=0x8049e68, eptr=0x8049e70,
newval=18446744073709551615, smodel=5, fmodel=0) at
/vol/gcc/src/hg/trunk/local/libatomic/cas_n.c:41
#4  0xfef823fc in libat_compare_exchange_8 (mptr=0x8049e68, eptr=0x8049e70,
newval=18446744073709551615, smodel=5, fmodel=0) at
/vol/gcc/src/hg/trunk/local/libatomic/cas_n.c:41

Seems to be infinite recursion.

  Rainer

[Bug other/53284] Several libatomic tests fail on 32-bit Solaris/x86

[rth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53284

--- Comment #1 from Richard Henderson <rth at gcc dot gnu.org> 2012-05-08 22:39:35 UTC ---
Can you investigate why configure decides that __atomic_compare_exchange_8
is implemented inline?  That it isn't inline is obvious from the recursion.

Was the configure change to CFLAGS in fact wrong?

[Bug other/53284] Several libatomic tests fail on 32-bit Solaris/x86

[ro at CeBiTec dot Uni-Bielefeld.DE]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53284

--- Comment #2 from ro at CeBiTec dot Uni-Bielefeld.DE <ro at CeBiTec dot Uni-Bielefeld.DE> 2012-05-09 11:45:10 UTC ---
> --- Comment #1 from Richard Henderson <rth at gcc dot gnu.org> 2012-05-08 22:39:35 UTC ---
> Can you investigate why configure decides that __atomic_compare_exchange_8
> is implemented inline?  That it isn't inline is obvious from the recursion.

That was the critical hint, thanks.  Comparing i386-pc-solaris2.10 and
i686-unknown-linux-gnu config.log, I see that in the Linux case the test
is run as a link test and includes -fno-sync-libcalls $XCFLAGS, while in
the Solaris case, it's an compile test and lacks all of them.

> Was the configure change to CFLAGS in fact wrong?

No, that's unrelated.

The following patch works for me and lets all tests in the above
configuration pass.  I've chosen to add to CFLAGS rather than adding
$XCFLAGS since otherwise we loose -fno-sync-libcalls.

Ok for mainline?

Thanks.
        Rainer


2012-05-09  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>

    * acinclude.m4 (LIBAT_TEST_ATOMIC_BUILTIN): Add -O0 -S to CFLAGS
    instead of overriding.
    * configure: Regenerate.

diff --git a/libatomic/acinclude.m4 b/libatomic/acinclude.m4
--- a/libatomic/acinclude.m4
+++ b/libatomic/acinclude.m4
@@ -67,7 +67,7 @@ AC_DEFUN([LIBAT_TEST_ATOMIC_BUILTIN],[
     else
       old_CFLAGS="$CFLAGS"
       # Compile unoptimized.
-      CFLAGS='-O0 -S'
+      CFLAGS="$CFLAGS -O0 -S"
       if AC_TRY_EVAL(ac_compile); then
         if grep __atomic_ conftest.s >/dev/null 2>&1 ; then
       eval $2=no

[Bug other/53284] Several libatomic tests fail on 32-bit Solaris/x86

[rth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53284

Richard Henderson <rth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
   Last reconfirmed|                            |2012-05-09
         AssignedTo|unassigned at gcc dot       |ro at gcc dot gnu.org
                   |gnu.org                     |
     Ever Confirmed|0                           |1

--- Comment #3 from Richard Henderson <rth at gcc dot gnu.org> 2012-05-09 18:00:29 UTC ---
Yep, that looks good.

[Bug other/53284] Several libatomic tests fail on 32-bit Solaris/x86

[ro at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53284

--- Comment #4 from Rainer Orth <ro at gcc dot gnu.org> 2012-05-10 09:11:14 UTC ---
Author: ro
Date: Thu May 10 09:11:05 2012
New Revision: 187366

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=187366
Log:
Always compile atomic builtin tests with $XCFLAGS

    PR other/53284
    * acinclude.m4 (LIBAT_TEST_ATOMIC_BUILTIN): Add -O0 -S to CFLAGS
    instead of overriding.
    * configure: Regenerate.

Modified:
    trunk/libatomic/ChangeLog
    trunk/libatomic/acinclude.m4
    trunk/libatomic/configure   (contents, props changed)

[Bug other/53284] Several libatomic tests fail on 32-bit Solaris/x86

[ro at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53284

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
                URL|                            |http://gcc.gnu.org/ml/gcc-p
                   |                            |atches/2012-05/msg00725.htm
                   |                            |l
         Resolution|                            |FIXED
   Target Milestone|---                         |4.8.0

--- Comment #5 from Rainer Orth <ro at gcc dot gnu.org> 2012-05-10 09:17:40 UTC ---
Fixed for 4.8.0.

[Bug other/53284] Several libatomic tests fail on 32-bit Solaris/x86

[dominiq at lps dot ens.fr]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53284

--- Comment #6 from Dominique d'Humieres <dominiq at lps dot ens.fr> 2012-05-10 12:17:17 UTC ---
For the record, r187366 fixes the same failures on x86_64-apple-darwin10.