Hi Mathieu I'd like to add some more detail. I now run our app using this pattern:
LD_PRELOAD=liblttng-ust-cyg-profile.so ./app On importing the trace into TraceCompass I see: "null analysis for LTTng-UST CallStack" Could the reason be the lttng commands I am using to capture UST and Kernel events: lttng enable-event --userspace 'lttng_ust_tracef:*' lttng enable-channel --kernel --session app_trace kernel_channel lttng enable-event --kernel --all --channel kernel_channel --session app_trace Best regards David On Wed, Jun 4, 2025 at 5:22 PM David Aldrich <david.aldrich.n...@gmail.com> wrote: > > Hi Mathieu > > > > Any idea what I am doing wrong please? > > > > AFAIK, the "LD_PRELOAD" environment variable is cleared by > > sudo when running its child process for security purposes. > > Thanks for your answer, that does help. However, I have now adjusted > the code so that sudo is not required, but when I import the trace the > UST-CallStacks are still strikethrough. > > Any thoughts why this is happening? > > I don't see any runtime errors whether or not I specify the prefix: > > LD_PRELOAD=liblttng-ust-cyg-profile.so > > Is that expected? > > Best regards, David
