On Thu, Jun 8, 2017 at 2:25 PM, Jeff Law <l...@redhat.com> wrote: > On 06/08/2017 04:24 AM, Christophe Lyon wrote: >> On 8 June 2017 at 11:57, Georg-Johann Lay <a...@gjlay.de> wrote: >>> On 05.06.2017 18:25, Jim Wilson wrote: >>>> >>>> On 06/01/2017 05:59 AM, Georg-Johann Lay wrote: >>>>> >>>>> Hi, when I am running the gcc testsuite in $builddir/gcc then >>>>> $ make check-gcc RUNTESTFLAGS='ubsan.exp' >>>>> comes up with spurious fails. >>>> >>>> >>>> This was discussed before, and the suspicion was that it was a linux >>>> kernel bug. There were multiple kernel fixes pointed at, it wasn't >>>> clear which one was required to fix it. >>>> >>>> I have Ubuntu 16.04 LTS on my laptop, and I see the problem. I can't >>>> run the ubsan testsuites with -j factor greater than one and get >>>> reproducible results. There may also be other ways to trigger the >>>> problem. >>>> >>>> See for instance the thread >>>> https://gcc.gnu.org/ml/gcc/2016-07/msg00117.html >>>> The first message in the thread from Andrew Pinski mentions that the log >>>> output is corrupted from apparent buffer overflow. >>>> >>>> Jim >>> >>> >>> >>> I have "Ubuntu 16.04.2 LTS". >>> >>> Asking this at DejaGNU's, I got the following pointer: >>> >>> https://lists.gnu.org/archive/html/dejagnu/2016-03/msg00034.html >>> >>> AFAIU there is a problem separating stdout and stderr? >>> >> >> Be careful, I'm not a dejagnu maintainer/developer :-) >> I just meant to say I had "similar" problems, but according to this >> thread, I'm not the only one :( > There was most definitely a linux kernel bug that affected the behavior > of "expect" used by dejagnu in the past. > > THe gcc.gnu.org reference to a message from Pinski is the right one -- > it identifies the problematical change in the kernel that mucked up > expect's behavior. > > In the thread you'll find a reference to: > > https://bugzilla.kernel.org/show_bug.cgi?id=96311 > > This has long since been fixed. BUt I have no idea what version of hte > kernel is in Ubuntu and whether or not it is subject to this problem.
I think 4.10 or 4.11 has the full fix. There was still some bugs even in 4.8 (which was the one included with Ubuntu 1604). I only say this is because I have a 4.8 kernel which sees the problem but a 4.11 kernel does not. The behavior I see with a non fixed kernel is that the guailty tests will not run at all. With the fixed kernel, it will run. Thanks, Andrew > > jeff
