1 files changed, 84 insertions, 0 deletions
diff --git a/community/elixir/bit-comp-works.patch b/community/elixir/bit-comp-works.patch
new file mode 100644
index 0000000000..6cda7edb0a
--- /dev/null
+++ b/community/elixir/bit-comp-works.patch
@@ -0,0 +1,84 @@
+From 141c3276857ac09bb1f378ed6842495bb0b0e57d Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Jos=C3=A9=20Valim?= <jose.valim@gmail.com>
+Date: Wed, 14 Mar 2018 21:45:13 +0100
+Subject: [PATCH] Ensure bitstring comprehensions work on OTP 20.3 (#7453)
+
+Closes #7452
+---
+ lib/elixir/lib/collectable.ex     |  3 +++
+ lib/elixir/src/elixir_erl_for.erl | 24 +++++++++++++++++-------
+ 2 files changed, 20 insertions(+), 7 deletions(-)
+
+diff --git a/lib/elixir/lib/collectable.ex b/lib/elixir/lib/collectable.ex
+index f7a35cd65e..495eb848cb 100644
+--- a/lib/elixir/lib/collectable.ex
++++ b/lib/elixir/lib/collectable.ex
+@@ -101,6 +101,9 @@ defimpl Collectable, for: BitString do
+       acc, {:cont, x} when is_bitstring(x) ->
+         <<IO.iodata_to_binary(acc)::bitstring, x::bitstring>>
+
++      acc, :done when is_bitstring(acc) ->
++        acc
++
+       acc, :done ->
+         IO.iodata_to_binary(acc)
+
+diff --git a/lib/elixir/src/elixir_erl_for.erl b/lib/elixir/src/elixir_erl_for.erl
+index e24da55a8b..5c4ce62c6d 100644
+--- a/lib/elixir/src/elixir_erl_for.erl
++++ b/lib/elixir/src/elixir_erl_for.erl
+@@ -21,7 +21,7 @@ translate(Meta, Args, Return, S) ->
+
+   case comprehension_expr(TInto, TExpr) of
+     {inline, TIntoExpr} ->
+-      {build_inline(Ann, TCases, TIntoExpr, TInto, TUniq, SF), SF};
++      build_inline(Ann, TCases, TIntoExpr, TInto, TUniq, SF);
+     {into, TIntoExpr} ->
+       build_into(Ann, TCases, TIntoExpr, TInto, TUniq, SF)
+   end.
+@@ -91,17 +91,17 @@ collect_filters([], Acc) ->
+
+ build_inline(Ann, Clauses, Expr, Into, Uniq, S) ->
+   case not Uniq and lists:all(fun(Clause) -> element(1, Clause) == bin end, Clauses) of
+-    true  -> build_comprehension(Ann, Clauses, Expr, Into);
++    true  -> {build_comprehension(Ann, Clauses, Expr, Into), S};
+     false -> build_inline_each(Ann, Clauses, Expr, Into, Uniq, S)
+   end.
+
+ build_inline_each(Ann, Clauses, Expr, false, Uniq, S) ->
+   InnerFun = fun(InnerExpr, _InnerAcc) -> InnerExpr end,
+-  build_reduce(Ann, Clauses, InnerFun, Expr, {nil, Ann}, Uniq, S);
++  {build_reduce(Ann, Clauses, InnerFun, Expr, {nil, Ann}, Uniq, S), S};
+ build_inline_each(Ann, Clauses, Expr, {nil, _} = Into, Uniq, S) ->
+   InnerFun = fun(InnerExpr, InnerAcc) -> {cons, Ann, InnerExpr, InnerAcc} end,
+   ReduceExpr = build_reduce(Ann, Clauses, InnerFun, Expr, Into, Uniq, S),
+-  elixir_erl:remote(Ann, lists, reverse, [ReduceExpr]);
++  {elixir_erl:remote(Ann, lists, reverse, [ReduceExpr]), S};
+ build_inline_each(Ann, Clauses, Expr, {bin, _, []}, Uniq, S) ->
+   {InnerValue, SV} = build_var(Ann, S),
+
+@@ -135,11 +135,21 @@ build_inline_each(Ann, Clauses, Expr, {bin, _, []}, Uniq, S) ->
+   end,
+
+   ReduceExpr = build_reduce(Ann, Clauses, InnerFun, Expr, {nil, Ann}, Uniq, SV),
+-  elixir_erl:remote(Ann, erlang, iolist_to_binary, [ReduceExpr]).
++
++  {{'case', Ann, ReduceExpr, [
++    {clause, Ann,
++     [InnerValue],
++     [[elixir_erl:remote(Ann, erlang, is_bitstring, [InnerValue])]],
++     [InnerValue]},
++    {clause, Ann,
++     [InnerValue],
++     [],
++     [elixir_erl:remote(Ann, erlang, iolist_to_binary, [InnerValue])]}
++  ]}, SV}.
+
+ build_into(Ann, Clauses, Expr, {map, _, []}, Uniq, S) ->
+-  ReduceExpr = build_inline_each(Ann, Clauses, Expr, {nil, Ann}, Uniq, S),
+-  {elixir_erl:remote(Ann, maps, from_list, [ReduceExpr]), S};
++  {ReduceExpr, SR} = build_inline_each(Ann, Clauses, Expr, {nil, Ann}, Uniq, S),
++  {elixir_erl:remote(Ann, maps, from_list, [ReduceExpr]), SR};
+ build_into(Ann, Clauses, Expr, Into, Uniq, S) ->
+   {Fun, SF}    = build_var(Ann, S),
+   {Acc, SA}    = build_var(Ann, SF),