diff --git a/mix.exs b/mix.exs
index 5dfe44967..997ce4a14 100644
--- a/mix.exs
+++ b/mix.exs
@@ -64,7 +64,7 @@ defmodule Mix.Tasks.Compile.Asn1 do
     Erlang.compile(manifest(), mappings, :asn1, :erl, opts[:force], fn
       input, output ->
         options = options ++ [:noobj, outdir: Erlang.to_erl_file(Path.dirname(output))]
-        result = :asn1ct.compile(Erlang.to_erl_file(input), options)
+        :asn1ct.compile(Erlang.to_erl_file(input), options)
         :ok
     end)
   end