Correct erlang:is_builtin/3 for apply/2 and yield/0

erlang:is_builtin(erlang, M, F) returns false for apply/2 and
yield/0. The documentation for erlang:is_builtin/3 says that it
returns true for BIFs that are implemented in C. apply/2 and
yield/0 are implemented in C (as BEAM instructions), and
therefore the correct return value is true.

Also see a similar argument that was made for apply/3 in the past:

    http://erlang.org/pipermail/erlang-bugs/2015-October/005101.html

https://bugs.erlang.org/browse/ERL-500

1 files changed, 12 insertions, 6 deletions

diff --git a/erts/emulator/test/bif_SUITE.erl b/erts/emulator/test/bif_SUITE.erl
index 146c37b118..e1b42e5d85 100644
--- a/erts/emulator/test/bif_SUITE.erl
+++ b/erts/emulator/test/bif_SUITE.erl
@@ -781,14 +781,20 @@ is_builtin(_Config) ->
 		       {F,A} <- M:module_info(exports)],
     Exp = ordsets:from_list(Exp0),
 
-    %% erlang:apply/3 is considered to be built-in, but is not
-    %% implemented as other BIFs.
+    %% Built-ins implemented as special instructions.
+    Instructions = [{erlang,apply,2},{erlang,apply,3},{erlang,yield,0}],
 
-    Builtins0 = [{erlang,apply,3}|erlang:system_info(snifs)],
+    Builtins0 = Instructions ++ erlang:system_info(snifs),
     Builtins = ordsets:from_list(Builtins0),
-    NotBuiltin = ordsets:subtract(Exp, Builtins),
-    _ = [true = erlang:is_builtin(M, F, A) || {M,F,A} <- Builtins],
-    _ = [false = erlang:is_builtin(M, F, A) || {M,F,A} <- NotBuiltin],
+
+    Fakes = [{M,F,42} || {M,F,_} <- Instructions],
+    All = ordsets:from_list(Fakes ++ Exp),
+    NotBuiltin = ordsets:subtract(All, Builtins),
+
+    _ = [{true,_} = {erlang:is_builtin(M, F, A),MFA} ||
+            {M,F,A}=MFA <- Builtins],
+    _ = [{false,_} = {erlang:is_builtin(M, F, A),MFA} ||
+            {M,F,A}=MFA <- NotBuiltin],
 
     ok.