[tor-bugs] #32053 [Applications/Tor Browser]: Tor Browser bundles based on Firefox 68 ESR are not reproducible (LLVM optimization issue)

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#32053: Tor Browser bundles based on Firefox 68 ESR are not reproducible (LLVM
optimization issue)
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 Reporter:  gk                                   |          Owner:  tbb-
                                                 |  team
     Type:  defect                               |         Status:  new
 Priority:  Immediate                            |      Milestone:
Component:  Applications/Tor Browser             |        Version:
 Severity:  Critical                             |     Resolution:
 Keywords:  TorBrowserTeam201911, tbb-9.0-must,  |  Actual Points:
  tbb-9.0-issues, tbb-regression,                |
  tbb-9.0.1-can, GeorgKoppen201911               |
Parent ID:                                       |         Points:
 Reviewer:                                       |        Sponsor:
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Comment (by gk):

 Replying to [comment:37 alexcrichton]:
 > Oh for `llvm-extract` I used the `-rfunc` argument which is a regex
 instead of an exact name,  like so: `llvm-extract before.bc
 -rfunc=17h5949677e2a2fd343E -o before-extract.bc`

 Thanks, that helped. However, I've tried to repro just doing the `-jump-
 threading` pass thousands of times on the same machine (kernel, glibc
 etc.), with the same clang version, essentially with the same script, as I
 reproduce the bug when running *all* the passes up to and including the
 problematic `-jump-threading` one: but I don't hit the bug that way, which
 seems to reproduce my results from comment:30. I wonder what we are
 missing here.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/32053#comment:38>
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