This is on Julia1.3.1, Mac 10.14.5
Activating environment at `~/myuser/...Project.toml`
[587475ba] Flux v0.10.3
[e88e6eb3] Zygote v0.4.10
julia> Pkg.add("Distributions")
Updating registry at `~/.julia/registries/General`
Updating git-repo `https://github.com/JuliaRegistries/General.git`
Resolving package versions...
ERROR: Unable to automatically install 'Rmath' from '/Users/myuser/.julia/packages/Rmath_jll/dkU4a/Artifacts.toml'
Stacktrace:
[1] #ensure_artifact_installed#42(::Pkg.BinaryPlatforms.Platform, ::Bool, ::typeof(Pkg.Artifacts.ensure_artifact_installed), ::String, ::Dict{String,Any}, ::String) at /Users/julia/buildbot/worker/package_macos64/build/usr/share/julia/stdlib/v1.3/Pkg/src/Artifacts.jl:873
[2] (::Pkg.Artifacts.var"#kw##ensure_artifact_installed")(::NamedTuple{(:platform, :verbose),Tuple{Pkg.BinaryPlatforms.MacOS,Bool}}, ::typeof(Pkg.Artifacts.ensure_artifact_installed), ::String, ::Dict{String,Any}, ::String) at ./none:0
[3] #ensure_all_artifacts_installed#43(::Pkg.BinaryPlatforms.Platform, ::Nothing, ::Bool, ::Bool, ::typeof(Pkg.Artifacts.ensure_all_artifacts_installed), ::String) at /Users/julia/buildbot/worker/package_macos64/build/usr/share/julia/stdlib/v1.3/Pkg/src/Artifacts.jl:919
[4] #ensure_all_artifacts_installed at /Users/julia/buildbot/worker/package_macos64/build/usr/share/julia/stdlib/v1.3/Pkg/src/Operations.jl:0 [inlined]
[5] #download_artifacts#78(::Pkg.BinaryPlatforms.MacOS, ::Bool, ::typeof(Pkg.Operations.download_artifacts), ::Array{String,1}) at /Users/julia/buildbot/worker/package_macos64/build/usr/share/julia/stdlib/v1.3/Pkg/src/Operations.jl:580
[6] #download_artifacts at ./none:0 [inlined]
[7] #download_artifacts#73(::Pkg.BinaryPlatforms.MacOS, ::Bool, ::typeof(Pkg.Operations.download_artifacts), ::Array{Pkg.Types.PackageSpec,1}) at /Users/julia/buildbot/worker/package_macos64/build/usr/share/julia/stdlib/v1.3/Pkg/src/Operations.jl:570
[8] (::Pkg.Operations.var"#kw##download_artifacts")(::NamedTuple{(:platform,),Tuple{Pkg.BinaryPlatforms.MacOS}}, ::typeof(Pkg.Operations.download_artifacts), ::Array{Pkg.Types.PackageSpec,1}) at ./none:0
[9] #add#112(::Bool, ::Pkg.BinaryPlatforms.MacOS, ::typeof(Pkg.Operations.add), ::Pkg.Types.Context, ::Array{Pkg.Types.PackageSpec,1}, ::Array{Base.UUID,1}) at /Users/julia/buildbot/worker/package_macos64/build/usr/share/julia/stdlib/v1.3/Pkg/src/Operations.jl:1017
[10] #add at ./none:0 [inlined]
[11] #add#25(::Bool, ::Pkg.BinaryPlatforms.MacOS, ::Base.Iterators.Pairs{Union{},Union{},Tuple{},NamedTuple{(),Tuple{}}}, ::typeof(Pkg.API.add), ::Pkg.Types.Context, ::Array{Pkg.Types.PackageSpec,1}) at /Users/julia/buildbot/worker/package_macos64/build/usr/share/julia/stdlib/v1.3/Pkg/src/API.jl:102
[12] add(::Pkg.Types.Context, ::Array{Pkg.Types.PackageSpec,1}) at /Users/julia/buildbot/worker/package_macos64/build/usr/share/julia/stdlib/v1.3/Pkg/src/API.jl:72
[13] #add#24 at /Users/julia/buildbot/worker/package_macos64/build/usr/share/julia/stdlib/v1.3/Pkg/src/API.jl:69 [inlined]
[14] add at /Users/julia/buildbot/worker/package_macos64/build/usr/share/julia/stdlib/v1.3/Pkg/src/API.jl:69 [inlined]
[15] #add#21 at /Users/julia/buildbot/worker/package_macos64/build/usr/share/julia/stdlib/v1.3/Pkg/src/API.jl:67 [inlined]
[16] add at /Users/julia/buildbot/worker/package_macos64/build/usr/share/julia/stdlib/v1.3/Pkg/src/API.jl:67 [inlined]
[17] #add#20(::Base.Iterators.Pairs{Union{},Union{},Tuple{},NamedTuple{(),Tuple{}}}, ::typeof(Pkg.API.add), ::String) at /Users/julia/buildbot/worker/package_macos64/build/usr/share/julia/stdlib/v1.3/Pkg/src/API.jl:66
[18] add(::String) at /Users/julia/buildbot/worker/package_macos64/build/usr/share/julia/stdlib/v1.3/Pkg/src/API.jl:66
[19] top-level scope at none:0