Undefined module warnings for mix-compiled erlang code

Hi all!

I’m quite a new entry in the elixir community, and coming from erlang i found an issue integrating a mixed erlang/elixir codebase.

When i compile elixir code calling an non-existing module

defmodule Xxx do

  def a() do


a very useful warning is reported:

warning: DoesNotExists.b/0 is undefined (module DoesNotExists is not available or is yet to be defined)

This is very nice, since there is 99% chance of this being a typo.

I lately found out that mix is also more than happy to compile whatever src/*.erl files i have in my source tree, and this comes quite handy since i have to interact with a quite extensive codebase of libraries using erlang macro/record etc.

What i find odd is the fact that i don’t get the same kind of warning for the erlang code, so an erlang module like the following does not report anything wrong:




It is also true that this is not a warning that the erlang compiler will report,
but when using rebar3 i can just call rebar3 xref to perform a fast check, without involving unit tests or dialyzer.

Apparently mix xref does not offer of the shelf a way to perform such checks on erlang code, or if it does it is not clear from the documentation.

Is there a way to perform such validation on the codebase or the only option is to implement a mix task mimicking the rebar3 xref command?


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