Thx for the reply. On Mon, Feb 20, 2023 at 1:36 PM Stuart Henderson <s...@spacehopper.org> wrote:
> On 2023/02/20 10:46, Stephan Somogyi wrote: > > On aarch64 on a RPi3, somewhere between 7.2-current GENERIC.MP#2028 and > > GENERIC.MP#2033, and the package snapshots that happened around the > #2033 > > time,something changed that causes persistent segfaulting while > executing a > > perl script that's been unchanged for a year. > > The kernel build numbers aren't really helpful in identifying when these > snapshots were built; dates would be better > I updated to 2028 on Feb 15 and 2033 on Feb 18, so whatever has gone awry happened in that window. I tend to pick up snapshots when the package snapshots update, so every 2-4 days. I do recall an instance of package snapshot updating around that time that looked like it updated everything installed, which made me wonder if clang had been updated, but it appears to still be on 13.0.0. > First off, assuming you're now on a system which is after the perl > update, make sure you updated all packages and don't have old XS modules > lying around; you should get no results from > > grep '@wantlib perl.22.0' /var/db/pkg/*/+CONTENTS > Nothing returned from that. > (Or if you've built your own Perl native extensions from outside of > packages then they'll want rebuilding) > I've not built any native extensions for this setup, but good to know. > > The segfault happens when python3 scripts are invoked from within the > perl > > script. I'm invoking the python3 scripts via system(); when I then SIGINT > > via Ctrl-C, the traceback is from within python3.10, suggesting that > > something that python is sub-launching might be causing the problem, but > my > > understanding of python internals is basically zero. > > > > If I manually invoke either of the python scripts with identical > > parameters, everything works, so it's not an innate problem with those > > scripts or their interaction with python3.10; it's something about how > > they're being invoked from perl. > > > > I've tried building minimal repro case perl scripts and am so far > > unsuccessful; everything works without segfaulting. > > > > I've done enough isolation work now that I'm running into my limits of > > knowledge and was curious whether this recent behavior rings a bell with > > anyone here. Grasping at straws, but could this have anything to do with > > the xonly work? > > > > Thanks for any suggestions for how to better identify the root cause and > > thus generate a more useful bug report. > > A backtrace from the segfault might give some clues (pkg_add gdb and > use the 'egdb' binary; the version of gdb that is in base is not really > useful in most cases any more) > If I debug the perl instance with egdb, I see the same litany of uninformative "Segmentation fault" lines that appear to be happening in python3, but nothing specifically from egdb. If I then apply egdb to the python3 invocation inside the perl script, it tells me that python3 (installed via pkg_add; nothing custom) has no symbols, and then proceeds to self-quit, whereupon I again just get line after line of segfaults. Thanks, s.
