beam.smp coredump when exiting riak

[jonmeredith]

When run with R15B against the current master branch, beam.smp coredumps on emulator exit.

[jonmeredith]

Reproducer, run with erl +A1 from the top level erlang_js dir t:run(). q(). will trigger

-module(t).
-compile([export_all]).

run() ->
    code:add_path("ebin"),
    ok = application:start(sasl),
    ok = application:start(erlang_js),
    true = (erlang:system_info(thread_pool_size) > 0),
    ThreadStack = 1,
    HeapSize = 1,
    js_driver:new(ThreadStack, HeapSize). 

[jonmeredith]

Smaller reproducer

% Have to add -compile([export_all]) to js_driver.erl
-module(t).
-compile([export_all]).
-define(DRIVER_NAME, "erlang_js_drv").

run() ->
    code:add_path("ebin"),
    ok = application:start(sasl),
    ok = application:start(erlang_js),
    true = (erlang:system_info(thread_pool_size) > 0),
    ThreadStack = 1,
    HeapSize = 1,
    js_driver:load_driver(),
    Port = open_port({spawn, ?DRIVER_NAME}, [binary]),
    js_driver:call_driver(Port, "ij", [ThreadStack, HeapSize], 5000),
    js_driver:define_js(Port, <<"avar.js">>, <<"var v;">>, 5000). %% This call is critical

No coredump unless define_js is called.

[jonmeredith]

Fixed in #25