ext/etc/extconf.rb in etc-1.1.0 vs ext/etc/extconf.rb in etc-1.2.0

@@ -45,8 +45,13 @@
 srcdir = File.expand_path("..", __FILE__)
 if !File.exist?("#{srcdir}/depend")
   %x[#{RbConfig.ruby} #{srcdir}/mkconstants.rb -o #{srcdir}/constdefs.h]
 end
 
+decl = [
+  "void rb_deprecate_constant(VALUE, const char *);",
+]
+have_func('rb_deprecate_constant(Qnil, "None")', [decl])
+
 $distcleanfiles << "constdefs.h"
 
 create_makefile("etc")