[tor-bugs] #25483 [Obfuscation/Snowflake]: Windows reproducible build of snowflake

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#25483: Windows reproducible build of snowflake
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 Reporter:  arlolra                |          Owner:  sukhbir
     Type:  project                |         Status:  assigned
 Priority:  High                   |      Milestone:
Component:  Obfuscation/Snowflake  |        Version:
 Severity:  Normal                 |     Resolution:
 Keywords:  TorBrowserTeam201805   |  Actual Points:
Parent ID:  #19001                 |         Points:
 Reviewer:                         |        Sponsor:
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Comment (by gk):

 Replying to [comment:36 sukhbir]:
 > Replying to [comment:34 gk]:
 > > That's reproducible on two different build machines for me. I worked
 around both errors on one of the machines my just getting rid of
 everything `webrtc` related and starting over in this regard. We should
 not need to do this, though. I therefore keep the second machine as-is for
 debugging purposes.
 >
 > Sorry, did you mean the errors you have are reproducible or the error I
 mentioned in #comment:24?

 I can reproduce the error in comment:34 on two different machines and
 that's what I meant.

 Over the weekend I tried to look more closely at it. So, updating to
 mingw-w64 `master` and GCC 6.4.0 does not help. Then I tried to build
 clang `master` and see whether we can verify the claim in comment:25 (and
 maybe be lucky because our bugs got fixed like last week :) ).

 I tried for a while to get the clang build going by setting
 `LLVM_FORCE_HEAD_REVISION` to `1`. It turns out that breaks the clang
 plugin compilation and other clang tools' compilation as well. Not
 compiling those gives a proper clang based on `master`, unfortunately
 requires the WebRTC build those missing clang tools.

 I then settled to use the latest prebuilt clang binaries (by messing with
 the `update.py` script (see:
 https://chromium.googlesource.com/chromium/src/tools/clang/+/master/scripts/update.py))
 using rev 332335 which is just ca. 400 commit behind the latest one. I am
 still getting the same errors as in comment:24.

 I guess it's time to look at the symbols...

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/25483#comment:37>
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