Regression: `eq`, `args` fails during `lift-trace`

[michaelbrownuc]

@ameily and I have both seen this issue with two binaries so far, args and eq. The details of the failure output are:

pipenv run python -m binrec.lift -vv "argsproj"
Loading .env environment variables…
10:41:32 DEBUG binrec.lift: extracting symbols from binary: s2e-out
10:41:32 DEBUG binrec.audit: subprocess.Popen: ('make', ['make', '-f', '/home/michaeldbrown/binrec-prerelease/scripts/s2eout_makefile', 'symbols'], '/home/michaeldbrown/binrec-prerelease/s2e/projects/argsproj/s2e-out', None)
make: 'symbols' is up to date.
10:41:32 DEBUG binrec.lift: cleaning captured bitcode: s2e-out
10:41:32 DEBUG binrec.lift: applying fixups to captured bitcode: s2e-out
10:41:32 DEBUG binrec.audit: subprocess.Popen: ('llvm-link-12', ['llvm-link-12', '-o', 'linked.bc', 'cleaned.bc', '/home/michaeldbrown/binrec-prerelease/runlib/custom-helpers.bc'], '/home/michaeldbrown/binrec-prerelease/s2e/projects/argsproj/s2e-out', None)
10:41:32 DEBUG binrec.lift: performing initially lifting of captured LLVM bitcode: s2e-out
[INFO] pruned 0 trivially dead references from successor lists
[INFO] pruned 0 trivially dead references from successor lists
[INFO] pruned 0 trivially dead references from successor lists
[INFO] pruned 0 trivially dead references from successor lists
[INFO] pruned 0 trivially dead references from successor lists
Traceback (most recent call last):
  File "/home/michaeldbrown/binrec-prerelease/binrec/lift.py", line 203, in _lift_bitcode
    binrec_lift.lift(
RuntimeError: block BB_8049160 stores PC 2148087152 but does not have BB_80093570 in its successor list. Did you remember to disable multithreading in qemu (-smp 1)

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/lib/python3.9/runpy.py", line 197, in _run_module_as_main
    return _run_code(code, main_globals, None,
  File "/usr/lib/python3.9/runpy.py", line 87, in _run_code
    exec(code, run_globals)
  File "/home/michaeldbrown/binrec-prerelease/binrec/lift.py", line 411, in <module>
    main()
  File "/home/michaeldbrown/binrec-prerelease/binrec/lift.py", line 406, in main
    lift_trace(args.project_name)
  File "/home/michaeldbrown/binrec-prerelease/binrec/lift.py", line 360, in lift_trace
    _lift_bitcode(merged_trace_dir)
  File "/home/michaeldbrown/binrec-prerelease/binrec/lift.py", line 210, in _lift_bitcode
    raise BinRecError(
binrec.errors.BinRecError: failed to perform initial lifting of LLVM bitcode: s2e-out: block BB_8049160 stores PC 2148087152 but does not have BB_80093570 in its successor list. Did you remember to disable multithreading in qemu (-smp 1)
error: Recipe `lift-trace` failed on line 251 with exit code 1

[michaelbrownuc]

@ameily - Can this be closed? I think your recent PRs may resolve issues here, unless this is related to the transient failures we still see on some tests that otherwise pass. Can you confirm, Thanks!

[ameily]

I am still seeing this intermittently on multiple samples, seemingly at random. So this, along with trailofbits/binrec-tob#33, are still present.

[ameily]

If I encountered this again I'll check to see if this is actually a side-effect of inconsistent trace info (#170)