From 842f600a93deca71e908ef5bb16e4e6aed519890 Mon Sep 17 00:00:00 2001
From: Nobuyoshi Nakada <nobu@ruby-lang.org>
Date: Wed, 18 Sep 2019 23:31:53 +0900
Subject: [PATCH] Look up the language module

Look up language module with `MakeMakefile.[]`, insted of a
accessing constant under that module directly, to get rid of
expose the constant to the toplevel inadvertently.
---
 ext/-test-/cxxanyargs/extconf.rb |  2 +-
 lib/mkmf.rb                      | 12 +++++++++++-
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/ext/-test-/cxxanyargs/extconf.rb b/ext/-test-/cxxanyargs/extconf.rb
index c1823a4042..7e2449a457 100644
--- a/ext/-test-/cxxanyargs/extconf.rb
+++ b/ext/-test-/cxxanyargs/extconf.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: false
 
-cxx = MakeMakefile::CXX
+cxx = MakeMakefile["C++"]
 
 ok = cxx.try_compile(<<~'begin', "") do |x|
   #include "ruby/config.h"
diff --git a/lib/mkmf.rb b/lib/mkmf.rb
index 8df6e9ad59..ce72668501 100644
--- a/lib/mkmf.rb
+++ b/lib/mkmf.rb
@@ -2776,7 +2776,17 @@ distclean: clean distclean-so distclean-static distclean-rb-default distclean-rb
 realclean: distclean
 "
 
-  module CXX
+  @lang = Hash.new(self)
+
+  def self.[](name)
+    @lang.fetch(name)
+  end
+
+  def self.[]=(name, mod)
+    @lang[name] = mod
+  end
+
+  self["C++"] = Module.new do
     include MakeMakefile
     extend self