1. Enhancements

Elixir

• [Kernel] Perform partial expansion of literals in module attributes
• [Kernel] Do not add compile-time dependencies for literals as defaults in Application.compile_env/3 inside module attributes
• [Macro] Add Macro.expand_literals/2 and Macro.expand_literals/3
• [System] Add :close_stdin to System.shell/2

Mix

• [mix test] Accept --all-warnings option

2. Bug fixes

Elixir

• [Kernel] Fix misleading warning when :uniq is given in for comprehensions and the result is unused
• [Kernel] Improve error message for when there is a conflicting struct and ignoring module conflict
• [Kernel] Do not delete @enforce_keys attribute after defstruct declaration
• [Kernel] Do not crash the checker on modules with missing :debug_info chunk
• [Macro] Fix error in Macro.to_string/2 when converting an AST with :erlang.binary_to_atom/2
• [String] Fix String.split/3 and String.next_grapheme/1 returning invalid results on invalid UTF-8 encoding
• [System] Do not close stdin by default in System.shell/2
• [URI] Do not return uri.port as :undefined in certain cases in URI.new/1

ExUnit

• [ExUnit.DocTest] Do not crash when both :moduledoc and functions are specified in :only

IEx

• [CLI] Fix invalid argument handling when --no-pry is given

Mix

• [mix format] Do not cache inputs from .formatter.exs so they are properly re-evaluted on every call