Update LLVM to fix nightly build failures

[dotdash]

No description provided.

[rust-highfive]

r? @nikomatsakis

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[eddyb]

@bors r+

[bors]

📌 Commit e8c398d has been approved by eddyb

[alexcrichton]

Out of curiosity, what were these build failures that were seen? Is this something we should be concerned about when using stock LLVM 3.7?

[alexcrichton]

Also, just FYI, but I think that future LLVM updates can drop rust-lang/llvm@3c88bf7 as the upstream bug was fixed in 3.8.

[alexcrichton]

@bors: p=1

Looks like this is why we haven't produced a nightly recently

[bors]

⌛ Testing commit e8c398d with merge 33f0920...

[bors]

☀️ Test successful - auto-linux-32-nopt-t, auto-linux-32-opt, auto-linux-64-nopt-t, auto-linux-64-opt, auto-linux-64-x-android-t, auto-mac-32-opt, auto-mac-64-nopt-t, auto-mac-64-opt, auto-win-gnu-32-nopt-t, auto-win-gnu-32-opt, auto-win-gnu-64-nopt-t, auto-win-gnu-64-opt, auto-win-msvc-32-opt, auto-win-msvc-64-opt