Bigs cause segfaults when precompiled and inlined

[ChrisRackauckas]

I made a repo to show this problem. Here's a copy of the current README:

This is a Julia repository to share a segfaulting problem. It's pretty simple, to cause the segfault, just do

Pkg.clone("https://github.com/ChrisRackauckas/BigsSegfault.jl")
using BigsSegfault
f(1.0,2.0)

The problem looks like it comes from Bigs inlining in precompilation. The entire package is:

__precompile__() ## Required in order to segfault

module BigsSegfault
const α = parse(BigFloat,"1.01")
f = (t,u) -> (α*u)

function fmaker(α=1.0)
  f(t,u) = α*u
  return f
end
export f,α,fmaker
end # module

The reason I put this in a package is because the segfaults do not happen if precompilation is disabled, or if f is defined in a manner such that α does not inline [for example, using

function fmaker(α=1.0)
  f(t,u) = α*u
  return f
end

and then using the f developed from there will not segfault].

using BigsSegfault
f2 = fmaker()
f2(1.0,2.0) # No segfault

Note that this segfault also requires Juno to be restarted (not just killing the current process, but the window has to be closed and re-opened).

This segfault problem also happens with inlined Rational{BigInt}, generic functions, and more. For more examples, check out the tests which are commented out in DifferentialEquations.jl with the mention "Bigs problem". Another example of this issue can be found on julia-users.

[yuyichao]

Dup of #15722