"Disposing the isolate that is entered by a thread" for some exotic objects

[bnoordhuis]

require "mini_racer"
puts MiniRacer::Context.new.eval("
var b = [0,97,115,109,1,0,0,0,1,26,5,80,0,95,0,80,0,95,1,127,0,96,0,1,110,96,1,100,2,1,111,96,0,1,100,3,3,4,3,3,2,4,7,26,2,12,99,114,101,97,116,101,83,116,114,117,99,116,0,1,7,114,101,102,70,117,110,99,0,2,9,5,1,3,0,1,0,10,23,3,8,0,32,0,20,2,251,27,11,7,0,65,12,251,0,1,11,4,0,210,0,11,0,44,4,110,97,109,101,1,37,3,0,11,101,120,112,111,114,116,101,100,65,110,121,1,12,99,114,101,97,116,101,83,116,114,117,99,116,2,7,114,101,102,70,117,110,99]
var o = new WebAssembly.Instance(new WebAssembly.Module(new Uint8Array(b))).exports
o.refFunc()(o.createStruct)
")

$ bundle exec ruby t.rb 
/usr/lib/ruby/3.0.0/json/common.rb:216:in `parse': 809: unexpected token at 'undefined' (JSON::ParserError)
        from /usr/lib/ruby/3.0.0/json/common.rb:216:in `parse'
        from /home/bnoordhuis/src/mini_racer/lib/mini_racer.rb:237:in `eval_unsafe'
        from /home/bnoordhuis/src/mini_racer/lib/mini_racer.rb:237:in `block (2 levels) in eval'
        from /home/bnoordhuis/src/mini_racer/lib/mini_racer.rb:358:in `timeout'
        from /home/bnoordhuis/src/mini_racer/lib/mini_racer.rb:236:in `block in eval'
        from /home/bnoordhuis/src/mini_racer/lib/mini_racer.rb:234:in `synchronize'
        from /home/bnoordhuis/src/mini_racer/lib/mini_racer.rb:234:in `eval'
        from t.rb:2:in `<main>'

#
# Fatal error in v8::Isolate::Dispose()
# Disposing the isolate that is entered by a thread
#

Trace/breakpoint trap (core dumped)

V8's JSON.stringify returns undefined, which Ruby's JSON parser rejects by calling rb_raise() and longjmping out of a lexical scope where we hold the v8::Locker