0.6: SEGFAULT on precompile

[dlfivefifty]

I'm experiencing a surprising SEGFAULT on precompile. Here is the setup:

Pkg.add("ApproxFun")
Pkg.clone("https://github.com/daanhb/Domains.jl")
Pkg.checkout("ApproxFun","domains-support-crash")
Pkg.checkout("Domains","approxfun-support-crash")

And here is the SEGFAULT:

julia> versioninfo()
Julia Version 0.6.0
Commit 903644385b (2017-06-19 13:05 UTC)
Platform Info:
  OS: macOS (x86_64-apple-darwin16.7.0)
  CPU: Intel(R) Core(TM) i7-7700HQ CPU @ 2.80GHz
  WORD_SIZE: 64
  BLAS: libgfortblas
  LAPACK: liblapack
  LIBM: libopenlibm
  LLVM: libLLVM-3.9.1 (ORCJIT, broadwell)

julia> using ApproxFun

julia> precompile(union, (ApproxFun.Chebyshev{Domains.ChebyshevInterval{Float64},Float64}, ApproxFun.Ultraspherical{Int64,Domains.ChebyshevInterval{Float64},Float64}))

signal (11): Segmentation fault: 11
while loading no file, in expression starting on line 0

Running it in julia-debug only helped marginally: the precompile doesn't SEGFAULT, but calling it did.

Unfortunately, my attempts to narrow it down got rid of the SEGFAULT, and I can't test on 0.7 because the underlying packages aren't up to date

[ViralBShah]

Please reopen if still an issue on 0.6.3. However, that is the last 0.6 release.