02:24 <renlord> hi, i'm very new to systemtap, is it possible to demangle C++ backtraces with systemtap?

02:26 <fche> stap doesn't have a built-in demangler - esp. given that the main part would probably have to run in ring-0 kernel so that could be tricky with preexisting code

02:26 <fche> but you can always just pipe the output through /usr/bin/c++filt

02:26 <renlord> thanks :)

03:17 <renlord> how about accessing C++ class variables in systemtap? is that possible? documentation only talks about local variables.

03:41 <renlord> while trying to print a local variable in a stap script, i got an error "semantic error: No cfa_ops supplied, but needed by DW_OP_call_frame_cfa: operator '@var'"

16:38 <plouj> hi, I'm trying to get systemtap to work an Ubuntu cosmic system and for some reason I'm getting a semantic error: no match for the syscall probe

16:39 <plouj> https://paste.fedoraproject.org/paste/EEJTGl8I5eucGsGK9x0eag

16:41 <wcohen> hi plouj, which version of systemtap are you using? There were a number of changes made in the newly release systemtap 4.0 systemtap tapset for supporting 4.17 kernels, https://lwn.net/Articles/768323/

16:41 <plouj> Systemtap translator/driver (version 3.3/0.170, Debian version 3.3-1) and my kernel is 4.18.0-10-generic

16:43 <wcohen> plouj, using systemtap 3.3 is likely causing the problem.

16:43 <plouj> :(

16:45 <fche> systemtap 4.0 was released a couple of weeks ago and should work fine on your kernel.

16:47 <plouj> not in the ubuntu repos :/

16:47 <wcohen> plouj, probably should file a bug to let debian/ubuntu developers should build a newer version of systemtap. you could build a local copy of systemtap in the meantime.