diff --git a/CHANGELOG.md b/CHANGELOG.md
index 98b50082bde..80317c57ace 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,12 +6,16 @@
 
 * Deprecations
   * [File] `File.stream_to!/3` is deprecated
+  * [GenFSM] `GenFSM` is deprecated
   * [Kernel] `%` for sigils is deprecated in favor of `~`
   * [Kernel] `is_range/1` and `is_regex/1` are deprecated in favor of `Range.range?/1` and `Regex.regex?/1`
   * [Stream] `Stream.after/1` is deprecated
   * [URI] `URI.decode_query/1` is deprecated in favor of `URI.decode_query/2` with explicit dict argument
   * [URI] Passing lists as key or values in `URI.encode_query/1` is deprecated
 
+* Backwards incompatible changes
+  * [Mix] Remove `MIX_GIT_FORCE_HTTPS` as Git itself already provides mechanisms for doing so
+
 # v0.12.4 (2014-02-12)
 
 * Enhancements
diff --git a/lib/elixir/lib/gen_fsm/behaviour.ex b/lib/elixir/lib/gen_fsm/behaviour.ex
index d377241c38c..ddd5d91b96c 100644
--- a/lib/elixir/lib/gen_fsm/behaviour.ex
+++ b/lib/elixir/lib/gen_fsm/behaviour.ex
@@ -166,6 +166,8 @@ defmodule GenFSM.Behaviour do
   @doc false
   defmacro __using__(_) do
     quote location: :keep do
+      IO.puts :stderr, "warning: GenFSM is deprecated and it will be removed in upcoming releases\n#{Exception.format_stacktrace}"
+
       @behaviour :gen_fsm
 
       @doc false
diff --git a/lib/elixir/test/elixir/gen_fsm/behaviour_test.exs b/lib/elixir/test/elixir/gen_fsm/behaviour_test.exs
deleted file mode 100644
index ec39e1986b0..00000000000
--- a/lib/elixir/test/elixir/gen_fsm/behaviour_test.exs
+++ /dev/null
@@ -1,43 +0,0 @@
-Code.require_file "../test_helper.exs", __DIR__
-
-defmodule GenFSM.BehaviourTest do
-  use ExUnit.Case
-
-  setup_all do
-    :error_logger.tty(false)
-    :ok
-  end
-
-  teardown_all do
-    :error_logger.tty(true)
-    :ok
-  end
-
-  defmodule Sample do
-    use GenFSM.Behaviour
-
-    def init(args) do
-      { :ok, :sample, args }
-    end
-  end
-
-  test "sync event stops server on unknown requests" do
-    Process.flag(:trap_exit, true)
-    assert { :ok, pid } = :gen_fsm.start_link(Sample, [:hello], [])
-
-    catch_exit(:gen_fsm.sync_send_all_state_event(pid, :unknown_request))
-    assert_receive { :EXIT, ^pid, {:bad_sync_event, :sample, :unknown_request} }
-  after
-    Process.flag(:trap_exit, false)
-  end
-
-  test "event stops server on unknown requests" do
-    Process.flag(:trap_exit, true)
-    assert { :ok, pid } = :gen_fsm.start_link(Sample, [:hello], [])
-
-    :gen_fsm.send_all_state_event(pid, :unknown_request)
-    assert_receive { :EXIT, ^pid, {:bad_event, :sample, :unknown_request} }
-  after
-    Process.flag(:trap_exit, false)
-  end
-end