File 4201-Don-t-require-compile-time-features-to-be-enabled-in.patch of Package erlang

From 18807814dbf097faf0b4fb26fa5e13bd6b4bd7bd Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bj=C3=B6rn=20Gustavsson?= <bjorn@erlang.org>
Date: Thu, 9 Feb 2023 10:50:36 +0100
Subject: [PATCH] Don't require compile-time features to be enabled in the
 runtime

Earlier during development of Erlang/OTP 26 we hard-coded the
`maybe_expr` feature to be always enable in the runtime system.
Remove that hack and no longer require any compile-time feature to be
enabled in the runtime system.
---
 erts/preloaded/ebin/erlang.beam | Bin 133156 -> 132772 bytes
 erts/preloaded/src/erlang.erl   |  29 +++++++++--------------------
 erts/test/erlc_SUITE.erl        |  15 ++++++---------
 lib/stdlib/src/erl_features.erl |  25 +------------------------
 4 files changed, 16 insertions(+), 53 deletions(-)

diff --git a/erts/preloaded/src/erlang.erl b/erts/preloaded/src/erlang.erl
index cb32ed8ff2..87ff9624c2 100644
--- a/erts/preloaded/src/erlang.erl
+++ b/erts/preloaded/src/erlang.erl
@@ -2336,26 +2336,15 @@ is_tuple(_Term) ->
               | {features_not_allowed, [atom()]}.
 load_module(Mod, Code) ->
     try
-        Allowed =
-            case erlang:module_loaded(erl_features) of
-                true ->
-                    erl_features:load_allowed(Code);
-                false -> ok
-            end,
-        case Allowed of
-            {not_allowed, NotEnabled} ->
-                {error, {features_not_allowed, NotEnabled}};
-            ok ->
-                case erlang:prepare_loading(Mod, Code) of
-                    {error,_}=Error ->
-                        Error;
-                    Prep when erlang:is_reference(Prep) ->
-                        case erlang:finish_loading([Prep]) of
-                            ok ->
-                                {module,Mod};
-                            {Error,[Mod]} ->
-                                {error,Error}
-                        end
+        case erlang:prepare_loading(Mod, Code) of
+            {error,_}=Error ->
+                Error;
+            Prep when erlang:is_reference(Prep) ->
+                case erlang:finish_loading([Prep]) of
+                    ok ->
+                        {module,Mod};
+                    {Error,[Mod]} ->
+                        {error,Error}
                 end
         end
     catch
diff --git a/erts/test/erlc_SUITE.erl b/erts/test/erlc_SUITE.erl
index a0417051b7..1149d8816d 100644
--- a/erts/test/erlc_SUITE.erl
+++ b/erts/test/erlc_SUITE.erl
@@ -840,9 +840,9 @@ features_macros(Config) when is_list(Config) ->
 
     true = erpc:call(Node1, erlang, module_loaded, [erl_features]),
 
-    %% We can't load this due to experimental_ftr_1 not being enabled
-    %% in the runtime
-    {error, {features_not_allowed, [experimental_ftr_1]}} =
+    %% Starting from OTP 26, compile-time features don't need to be
+    %% enabled in the runtime system.
+    {module, f_macros} =
         erpc:call(Node1, code, load_file, [f_macros]),
     %% Check features enabled during compilation
     [approved_ftr_1, approved_ftr_2, experimental_ftr_1] =
@@ -934,8 +934,6 @@ features_all(Config) when is_list(Config) ->
                            "-disable-feature", "all"]),
     %% Check features enabled during compilation
     [approved_ftr_2] = erpc:call(Node2, erl_features, used, [foo]),
-    {error, {features_not_allowed, [approved_ftr_2]}} =
-        erpc:call(Node2, code, load_file, [foo]),
     peer:stop(Peer2),
 
     ok.
diff --git a/lib/stdlib/src/erl_features.erl b/lib/stdlib/src/erl_features.erl
index ac2ecd3c37..ffccfcbfb3 100644
--- a/lib/stdlib/src/erl_features.erl
+++ b/lib/stdlib/src/erl_features.erl
@@ -26,7 +26,6 @@
          short/1,
          long/1,
          enabled/0,
-         load_allowed/1,
          keywords/0,
          keywords/1,
          keyword_fun/2,
@@ -423,32 +423,6 @@ keywords() ->
 set_keywords(Words) ->
     persistent_term:put({?MODULE, keywords}, Words).
 
-%% Check that any features used in the module are enabled in the
-%% runtime system.  If not, return
-%%  {not_allowed, <list of not enabled features>}.
--spec load_allowed(binary()) -> ok | {not_allowed, [feature()]}.
-load_allowed(Binary) ->
-    case erts_internal:beamfile_chunk(Binary, "Meta") of
-        undefined ->
-            ok;
-        Meta ->
-            MetaData = erlang:binary_to_term(Meta),
-            case proplists:get_value(enabled_features, MetaData) of
-                undefined ->
-                    ok;
-                Used ->
-                    Enabled = enabled(),
-                    case lists:filter(fun(UFtr) ->
-                                              not lists:member(UFtr, Enabled)
-                                      end,
-                                      Used) of
-                        [] -> ok;
-                        NotEnabled ->
-                            {not_allowed, NotEnabled}
-                    end
-            end
-    end.
-
 %% Return features used by module or beam file
 -spec used(module() | file:filename()) -> [feature()].
 used(Module) when is_atom(Module) ->
-- 
2.35.3