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Steps to reproduce:

Download concurrent-extra-0.7.0.12 and add the following stack.yaml file:

resolver: nightly-2018-04-04
system-ghc: true
compiler-check: newer-minor

Then run:

> ghc --version
The Glorious Glasgow Haskell Compilation System, version 8.4.1.20180329

> stack build --library-profiling
concurrent-extra-0.7.0.12: build (lib)
Preprocessing library for concurrent-extra-0.7.0.12..
Building library for concurrent-extra-0.7.0.12..
[7 of 8] Compiling Control.Concurrent.Broadcast ( Control/Concurrent/Broadcast.hs, .stack-work/dist/x86_64-linux/Cabal-2.2.0.1/build/Control/Concurrent/Broadcast.p_o )
ghc: panic! (the 'impossible' happened)
  (GHC version 8.4.1.20180329 for x86_64-unknown-linux):
	collectNBinders
  1
  Call stack:
      CallStack (from HasCallStack):
        callStackDoc, called at compiler/utils/Outputable.hs:1150:37 in ghc:Outputable
        pprPanic, called at compiler/coreSyn/CoreSyn.hs:2189:39 in ghc:CoreSyn

Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug


--  While building custom Setup.hs for package concurrent-extra-0.7.0.12 using:
      /home/local/ANT/ericcro/.stack/setup-exe-cache/x86_64-linux/Cabal-simple_mPHDZzAJ_2.2.0.1_ghc-8.4.1.20180329 --builddir=.stack-work/dist/x86_64-linux/Cabal-2.2.0.1 build lib:concurrent-extra --ghc-options " -ddump-hi -ddump-to-file -fdiagnostics-color=always"
    Process exited with code: ExitFailure 1