Start elixir config code only if elixir was enabled in configure script

rebar.config

@@ -74,6 +74,7 @@
             {if_var_true, debug, debug_info},
             {if_var_true, roster_gateway_workaround, {d, 'ROSTER_GATWAY_WORKAROUND'}},
             {if_var_match, db_type, mssql, {d, 'mssql'}},
+            {if_var_true, elixir, {d, 'ELIXIR_ENABLED'}},
             {if_var_true, erlang_deprecated_types, {d, 'ERL_DEPRECATED_TYPES'}},
             {if_var_true, hipe, native},
             {src_dirs, [asn1, src,

src/ejabberd_app.erl

@@ -255,7 +255,12 @@ register_elixir_config_hooks() ->
   end.
 
 start_elixir_application() ->
+    case ejabberd_config:is_elixir_enabled() of
+	true ->
 	    case application:ensure_started(elixir) of
 		ok -> ok;
 		{error, _Msg} -> ?ERROR_MSG("Elixir application not started.", [])
+	    end;
+	_ ->
+	    ok
     end.

src/ejabberd_config.erl

@@ -37,7 +37,8 @@
          prepare_opt_val/4, convert_table_to_binary/5,
          transform_options/1, collect_options/1, default_db/2,
          convert_to_yaml/1, convert_to_yaml/2, v_db/2,
-         env_binary_to_list/2, opt_type/1, may_hide_data/1]).
+         env_binary_to_list/2, opt_type/1, may_hide_data/1,
+	 is_elixir_enabled/0]).
 
 -export([start/2]).
 
@@ -148,12 +149,17 @@ read_file(File) ->
                      {include_modules_configs, true}]).
 
 read_file(File, Opts) ->
-    Terms1 = case 'Elixir.Ejabberd.ConfigUtil':is_elixir_config(File) of
+    Terms1 = case is_elixir_enabled() of
+		 true ->
+		     case 'Elixir.Ejabberd.ConfigUtil':is_elixir_config(File) of
 			 true ->
 			     'Elixir.Ejabberd.Config':init(File),
 			     'Elixir.Ejabberd.Config':get_ejabberd_opts();
 			 false ->
 			     get_plain_terms_file(File, Opts)
+		     end;
+		 false ->
+		     get_plain_terms_file(File, Opts)
 	     end,
     Terms_macros = case proplists:get_bool(replace_macros, Opts) of
                        true -> replace_macros(Terms1);
@@ -1049,9 +1055,22 @@ replace_modules(Modules) ->
 %% Elixir module naming
 %% ====================
 
+-ifdef(ELIXIR_ENABLED).
+is_elixir_enabled() ->
+    true.
+-else.
+is_elixir_enabled() ->
+    false.
+-endif.
+
 is_using_elixir_config() ->
+    case is_elixir_enabled() of
+	true ->
 	    Config = get_ejabberd_config_path(),
-  'Elixir.Ejabberd.ConfigUtil':is_elixir_config(Config).
+	    'Elixir.Ejabberd.ConfigUtil':is_elixir_config(Config);
+       false ->
+	    false
+    end.
 
 %% If module name start with uppercase letter, this is an Elixir module:
 is_elixir_module(Module) ->