Elixir: Elixir 1.4.5 not compatible with Erlang 19 on MacOS?

[sashaafm]

Environment

• Elixir & Erlang versions (elixir --version): Elixir 1.4.5 and Erlang/OTP 20
• Operating system: MacOS Sierra

Current behavior

Installed elixir 1.4.5 through brew using brew install elixir.

When trying to run iex I get this crash dump:

2017-06-29 11:45:58 Loading of ~ts failed: ~p

    "/usr/local/Cellar/elixir/1.4.5/bin/../lib/iex/ebin/Elixir.IEx.CLI.beam"
    badfile
2017-06-29 11:45:58 ~s~n
    "beam/beam_load.c(1287): Error loading module 'Elixir.IEx.CLI':\n  mandatory chunk of type 'Atom' not found\n\n"
2017-06-29 11:45:58 crash_report
    initial_call: {supervisor_bridge,user_sup,['Argument__1']}
    pid: <0.47.0>
    registered_name: []
    error_info: {exit,{undef,[{'Elixir.IEx.CLI',start,[],[]},{user_sup,start_user,3,[{file,"user_sup.erl"},{line,100}]},{user_sup,init,1,[{file,"user_sup.erl"},{line,49}]},{supervisor_bridge,init,1,[{file,"supervisor_bridge.erl"},{line,80}]},{gen_server,init_it,6,[{file,"gen_server.erl"},{line,328}]},{proc_lib,init_p_do_apply,3,[{file,"proc_lib.erl"},{line,247}]}]},[{gen_server,init_it,6,[{file,"gen_server.erl"},{line,352}]},{proc_lib,init_p_do_apply,3,[{file,"proc_lib.erl"},{line,247}]}]}
    ancestors: [kernel_sup,<0.34.0>]
    messages: []
    links: [<0.35.0>]
    dictionary: []
    trap_exit: true
    status: running
    heap_size: 610
    stack_size: 27
    reductions: 144
2017-06-29 11:45:58 supervisor_report
    supervisor: {local,kernel_sup}
    errorContext: start_error
    reason: {undef,[{'Elixir.IEx.CLI',start,[],[]},{user_sup,start_user,3,[{file,"user_sup.erl"},{line,100}]},{user_sup,init,1,[{file,"user_sup.erl"},{line,49}]},{supervisor_bridge,init,1,[{file,"supervisor_bridge.erl"},{line,80}]},{gen_server,init_it,6,[{file,"gen_server.erl"},{line,328}]},{proc_lib,init_p_do_apply,3,[{file,"proc_lib.erl"},{line,247}]}]}
    offender: [{pid,undefined},{id,user},{mfargs,{user_sup,start,[]}},{restart_type,temporary},{shutdown,2000},{child_type,supervisor}]
2017-06-29 11:45:58 crash_report
    initial_call: {application_master,init,['Argument__1','Argument__2','Argument__3','Argument__4']}
    pid: <0.33.0>
    registered_name: []
    error_info: {exit,{{shutdown,{failed_to_start_child,user,{undef,[{'Elixir.IEx.CLI',start,[],[]},{user_sup,start_user,3,[{file,"user_sup.erl"},{line,100}]},{user_sup,init,1,[{file,"user_sup.erl"},{line,49}]},{supervisor_bridge,init,1,[{file,"supervisor_bridge.erl"},{line,80}]},{gen_server,init_it,6,[{file,"gen_server.erl"},{line,328}]},{proc_lib,init_p_do_apply,3,[{file,"proc_lib.erl"},{line,247}]}]}}},{kernel,start,[normal,[]]}},[{application_master,init,4,[{file,"application_master.erl"},{line,134}]},{proc_lib,init_p_do_apply,3,[{file,"proc_lib.erl"},{line,247}]}]}
    ancestors: [<0.32.0>]
    messages: [{'EXIT',<0.34.0>,normal}]
    links: [<0.32.0>,<0.31.0>]
    dictionary: []
    trap_exit: true
    status: running
    heap_size: 610
    stack_size: 27
    reductions: 169
2017-06-29 11:45:58 std_info
    application: kernel
    exited: {{shutdown,{failed_to_start_child,user,{undef,[{'Elixir.IEx.CLI',start,[],[]},{user_sup,start_user,3,[{file,"user_sup.erl"},{line,100}]},{user_sup,init,1,[{file,"user_sup.erl"},{line,49}]},{supervisor_bridge,init,1,[{file,"supervisor_bridge.erl"},{line,80}]},{gen_server,init_it,6,[{file,"gen_server.erl"},{line,328}]},{proc_lib,init_p_do_apply,3,[{file,"proc_lib.erl"},{line,247}]}]}}},{kernel,start,[normal,[]]}}
    type: permanent
{"Kernel pid terminated",application_controller,"{application_start_failure,kernel,{{shutdown,{failed_to_start_child,user,{undef,[{'Elixir.IEx.CLI',start,[],[]},{user_sup,start_user,3,[{file,\"user_sup.erl\"},{line,100}]},{user_sup,init,1,[{file,\"user_sup.erl\"},{line,49}]},{supervisor_bridge,init,1,[{file,\"supervisor_bridge.erl\"},{line,80}]},{gen_server,init_it,6,[{file,\"gen_server.erl\"},{line,328}]},{proc_lib,init_p_do_apply,3,[{file,\"proc_lib.erl\"},{line,247}]}]}}},{kernel,start,[normal,[]]}}}"}
Kernel pid terminated (application_controller) ({application_start_failure,kernel,{{shutdown,{failed_to_start_child,user,{undef,[{'Elixir.IEx.CLI',start,[],[]},{user_sup,start_user,3,[{file,"user_sup.

Crash dump is being written to: erl_crash.dump...done

If I upgrade Erlang to version 20 it works again.

Expected behavior

IEx should launch normally.

[michalmuskala]

Code compiled on OTP 20 cannot run on OTP 19 (the reverse is perfectly possible, though).

[josevalim]

Yes, either you compiled the code and swapped OTP versions OR homebrew pre-compiled the code on 20 (which then means they should require OTP 20).

[samacs]

@sashaafm I had the same issue. Just for the record, I had erlang@19 installed, might be because I installed rabbitmq. I just did brew uninstall erlang@19 && brew update && brew install elixir and that's it.