[ROOT6 IBs] Unit test testUCTUnpackerfailed with segmentation violation

[aandvalenzuela]

Unit test testUCTUnpacker (module EventFilter/L1TXRawToDigi) failed with a segmentation violation in the latest ROOT6 IBs. Here is the stacktrace:

 
===== Test "testUCTUnpacker" ====
cat: src/EventFilter/L1TXRawToDigi/test/event_test1.txt: No such file or directory
%MSG-e UCTDAQRawData: 
CDF Header does not seem to be correct0x153700000005; but continuing!
%MSG

AMC Payload Header:
Data Length.. = 0
BXID......... = 0
L1ID......... = 00000000
AMC No ...... = 0
Layer-1 Phi.. = 0
Orbit No..... = 0
AMC Payload Trailer:

 *** Break *** segmentation violation
Data Length.. = 


===========================================================
There was a crash (kSigSegmentationViolation).
This is the entire stack trace of all threads:
===========================================================
#0  0x00001537720395db in waitpid () from /lib64/libc.so.6
#1  0x0000153771f9bce7 in do_system () from /lib64/libc.so.6
#2  0x00001537736a980c in TUnixSystem::Exec (this=0x1d430c0, shellcmd=0x2e83eb0 "/cvmfs/cms-ib.cern.ch/sw/x86_64/nweek-02792/el8_amd64_gcc11/lcg/root/6.29.01-e50d353bab9bcfd48d79a72b6af74b45/etc/gdb-backtrace.sh 2721593 1>&2") at /data/cmsbld/jenkins/workspace/build-any-ib/w/BUILD/el8_amd64_gcc11/lcg/root/6.29.01-e50d353bab9bcfd48d79a72b6af74b45/root-6.29.01/core/unix/src/TUnixSystem.cxx:2121
#3  0x00001537736aa0ad in TUnixSystem::StackTrace (this=0x1d430c0) at /data/cmsbld/jenkins/workspace/build-any-ib/w/BUILD/el8_amd64_gcc11/lcg/root/6.29.01-e50d353bab9bcfd48d79a72b6af74b45/root-6.29.01/core/unix/src/TUnixSystem.cxx:2412
#4  0x00001537736adae8 in TUnixSystem::DispatchSignals (this=0x1d430c0, sig=kSigSegmentationViolation) at /data/cmsbld/jenkins/workspace/build-any-ib/w/BUILD/el8_amd64_gcc11/lcg/root/6.29.01-e50d353bab9bcfd48d79a72b6af74b45/root-6.29.01/core/unix/src/TUnixSystem.cxx:3632
#5  0x00001537736a59d8 in SigHandler (sig=kSigSegmentationViolation) at /data/cmsbld/jenkins/workspace/build-any-ib/w/BUILD/el8_amd64_gcc11/lcg/root/6.29.01-e50d353bab9bcfd48d79a72b6af74b45/root-6.29.01/core/unix/src/TUnixSystem.cxx:403
#6  0x00001537736ad9eb in sighandler (sig=11) at /data/cmsbld/jenkins/workspace/build-any-ib/w/BUILD/el8_amd64_gcc11/lcg/root/6.29.01-e50d353bab9bcfd48d79a72b6af74b45/root-6.29.01/core/unix/src/TUnixSystem.cxx:3603
#7  <signal handler called>
#8  0x0000000000402a5f in main ()
===========================================================


The lines below might hint at the cause of the crash. If you see question
marks as part of the stack trace, try to recompile with debugging information
enabled and export CLING_DEBUG=1 environment variable before running.
You may get help by asking at the ROOT forum https://root.cern/forum
preferably using the command (.forum bug) in the ROOT prompt.
Only if you are really convinced it is a bug in ROOT then please submit a
report at https://root.cern/bugs or (preferably) using the command (.gh bug) in
the ROOT prompt. Please post the ENTIRE stack trace
from above as an attachment in addition to anything else
that might help us fixing this issue.
===========================================================
#8  0x0000000000402a5f in main ()
===========================================================



---> test testUCTUnpacker had ERRORS
TestTime:9
^^^^ End Test testUCTUnpacker ^^^^
>> Tests for package EventFilter/L1TXRawToDigi ran.

Thanks!
Andrea.

[cmsbuild]

A new Issue was created by @aandvalenzuela Andrea Valenzuela.

@Dr15Jones, @perrotta, @dpiparo, @rappoccio, @makortel, @smuzaffar can you please review it and eventually sign/assign? Thanks.

cms-bot commands are listed here

[aandvalenzuela]

New occurrence in the latest IBs.

[aandvalenzuela]

Also failing in ROOT628 IBs.

[Dr15Jones]

This does not appear to actually be ROOT related. The problem is when SCRAM changed the testing infrastructure to have tests run in their own test directories rather than run from the root directory of the work area it silently broke this unit test. One can see it by the error printed at the beginning of the output of the test

cat: src/EventFilter/L1TXRawToDigi/test/event_test1.txt: No such file or directory

The unit test than precedes to process an empty input (since the results of cat are piped to the test binary) which leads to the test ultimately reading from uninitialized memory (since the memory is expected to be filled from the input).

[Dr15Jones]

I have a fix coming which fixes both the handling of an empty input and the change to SCRAM for testing.

[Dr15Jones]

See #42222

[aandvalenzuela]

Thanks @Dr15Jones|

[iarspider]

please close

The issue was solved in #42222