Is this by design:
| | |_| | | | (_| | | Version 0.6.0-dev.1746 (2016-12-29 05:44 UTC)
_/ |\__'_|_|_|\__'_| | Commit 07b7a7f (3 days old master)
|__/ | x86_64-apple-darwin13.4.0
julia> sort([big(3), big(2)])
ERROR: MethodError: no method matching sub_with_overflow(::BigInt, ::BigInt)
in #sort!#7(::Base.Sort.QuickSortAlg, ::Function, ::Function, ::Bool, ::Base.Order.ForwardOrdering, ::Function, ::Array{BigInt,1}) at ./sort.jl:445
in #sort#8(::Array{Any,1}, ::Function, ::Array{BigInt,1}) at ./sort.jl:483
in sort(::Array{BigInt,1}) at ./sort.jl:483
Sorting BigFloat works, and both work with earlier versions of Julia.