Raise for is_record guards, closes #10436

Author: josevalim

lib/elixir/src/elixir_rewrite.erl

@@ -327,6 +327,10 @@ guard_rewrite(Receiver, DotMeta, Right, Meta, Args) ->
     _ -> {error, {invalid_guard, Receiver, Right, length(Args)}}
   end.
 
+%% erlang:is_record/2-3 are compiler guards in Erlang which we
+%% need to explicitly forbid as they are allowed in erl_internal.
+allowed_guard(is_record, 2) -> false;
+allowed_guard(is_record, 3) -> false;
 allowed_guard(Right, Arity) ->
   erl_internal:guard_bif(Right, Arity) orelse elixir_utils:guard_op(Right, Arity).
 

lib/elixir/test/elixir/kernel/guard_test.exs

@@ -310,6 +310,22 @@ defmodule Kernel.GuardTest do
         end
       end
 
+      assert_raise CompileError,
+                   ~r"cannot invoke remote function :erlang\.is_record/2 inside guards",
+                   fn ->
+                     defmodule IsRecord2Usage do
+                       defguard foo(rec) when :erlang.is_record(rec, :tag)
+                     end
+                   end
+
+      assert_raise CompileError,
+                   ~r"cannot invoke remote function :erlang\.is_record/3 inside guards",
+                   fn ->
+                     defmodule IsRecord3Usage do
+                       defguard foo(rec) when :erlang.is_record(rec, :tag, 7)
+                     end
+                   end
+
       assert_raise CompileError,
                    ~r"cannot invoke remote function :erlang\.\+\+/2 inside guards",
                    fn ->