User defined types with the name `record` fail to compile in 1.8.0-rc.0

[sneako]

Environment

• Elixir & Erlang/OTP versions (elixir --version):

Erlang/OTP 21 [erts-10.1.3] [source] [64-bit] [smp:8:8] [ds:8:8:10] [async-threads:1] [hipe]

Elixir 1.8.0 (compiled with Erlang/OTP 21)

• Operating system: Fedora 29

Current behavior

You can no longer create a user defined type with the name record.
Found this bug when compiling cachex which gave the following error:

== Compilation error in file lib/cachex/spec/validator.ex ==
** (CompileError) lib/cachex/spec/validator.ex:36: invalid record specification, expected the record name to be an atom
    (elixir) lib/kernel/typespec.ex:875: Kernel.Typespec.compile_error/2
    (elixir) lib/enum.ex:1431: Enum."-map_reduce/3-lists^mapfoldl/2-0-"/3
    (elixir) lib/enum.ex:1431: Enum."-map_reduce/3-lists^mapfoldl/2-0-"/3
    (elixir) lib/kernel/typespec.ex:927: Kernel.Typespec.fn_args/5
    (elixir) lib/kernel/typespec.ex:913: Kernel.Typespec.fn_args/6
    (elixir) lib/kernel/typespec.ex:366: Kernel.Typespec.translate_spec/8
    (elixir) lib/enum.ex:1431: Enum."-map_reduce/3-lists^mapfoldl/2-0-"/3
    (elixir) lib/kernel/typespec.ex:223: Kernel.Typespec.translate_typespecs_for_module/2

Expected behavior

Users should be able to define their own types with the name record as they were able to in previous versions of Elixir.

Minimal Example

defmodule Bug do
  @type record :: binary
  @spec foo?(record) :: boolean
  def foo?(_), do: true
end

Produces:

$ elixir bug.exs 
** (CompileError) bug.exs:3: invalid record specification, expected the record name to be an atom
    (elixir) lib/kernel/typespec.ex:875: Kernel.Typespec.compile_error/2
    (elixir) lib/enum.ex:1431: Enum."-map_reduce/3-lists^mapfoldl/2-0-"/3
    (elixir) lib/kernel/typespec.ex:927: Kernel.Typespec.fn_args/5
    (elixir) lib/kernel/typespec.ex:913: Kernel.Typespec.fn_args/6
    (elixir) lib/kernel/typespec.ex:366: Kernel.Typespec.translate_spec/8
    (elixir) lib/enum.ex:1431: Enum."-map_reduce/3-lists^mapfoldl/2-0-"/3
    (elixir) lib/kernel/typespec.ex:223: Kernel.Typespec.translate_typespecs_for_module/2

[Gazler]

I'd guess due to this commit da561ca#diff-6de4b356bc9d4e3d07f1e5731fbe7d23

[josevalim]

Yeah, the check should only run on record/1 (which should be unconditionally expanded to record(arg, [])) and record/2 but our catch all clause there is picking all :record calls.