Have you tried an strace to see if it tells you who is sending the signal? On Tue, Dec 4, 2018 at 6:49 PM Jonas Devlieghere via lldb-dev < lldb-dev@lists.llvm.org> wrote:
> Hi everyone, > > Since we switched to lit as the test driver we've been seeing it getting > killed as the result of a SIGHUP signal. The problem doesn't reproduce on > every machine and there seems to be a correlation between number of > occurrences and thread count. > > Davide and Raphael spent some time narrowing down what particular test is > causing this and it seems that TestChangeProcessGroup.py is always > involved. However it never reproduces when running just this test. I was > able to reproduce pretty consistently with the following filter: > > ./bin/llvm-lit ../llvm/tools/lldb/lit/Suite/ --filter="process" > > Bisecting the test itself didn't help much, the problem reproduces as soon > as we attach to the inferior. > > At this point it is still not clear who is sending the SIGHUP and why it's > reaching the lit test driver. Fred suggested that it might have something > to do with process groups (which would be an interesting coincidence given > the previously mentioned test) and he suggested having the test run in > different process groups. Indeed, adding a call to os.setpgrp() in lit's > executeCommand and having a different process group per test prevent us > from seeing this. Regardless of this issue I think it's reasonable to have > tests run in their process group, so if nobody objects I propose adding > this to lit in llvm. > > Still, I'd like to understand where the signal is coming from and fix the > root cause in addition to the symptom. Maybe someone here has an idea of > what might be going on? > > Thanks, > Jonas > > PS > > 1. There's two places where we send a SIGHUP ourself, with that code > removed we still receive the signal, which suggests that it might be coming > from Python or the OS. > 2. If you're able to reproduce you'll see that adding an early return > before the attach in TestChangeProcessGroup.py hides/prevents the problem. > Moving the return down one line and it pops up again. > _______________________________________________ > lldb-dev mailing list > lldb-dev@lists.llvm.org > http://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-dev >
_______________________________________________ lldb-dev mailing list lldb-dev@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-dev
