diff --git a/tool/ruby_vm/helpers/c_escape.rb b/tool/ruby_vm/helpers/c_escape.rb
index 088df1562e..2f73b8889f 100644
--- a/tool/ruby_vm/helpers/c_escape.rb
+++ b/tool/ruby_vm/helpers/c_escape.rb
@@ -118,3 +118,11 @@ module RubyVM::CEscape
   }.freeze
   private_constant :RString2CStr
 end
+
+unless defined? ''.b
+  class String
+    def b
+      return dup.force_encoding 'binary'
+    end
+  end
+end
diff --git a/tool/ruby_vm/helpers/dumper.rb b/tool/ruby_vm/helpers/dumper.rb
index 3ba7310f56..2d6bb269f6 100644
--- a/tool/ruby_vm/helpers/dumper.rb
+++ b/tool/ruby_vm/helpers/dumper.rb
@@ -25,7 +25,7 @@ class RubyVM::Dumper
   end
 
   def new_erb spec
-    path  = Pathname.new __dir__
+    path  = Pathname.new(__FILE__).realpath.dirname
     path += '../views'
     path += spec
     src   = path.read mode: 'rt:utf-8:utf-8'
@@ -88,8 +88,8 @@ class RubyVM::Dumper
     @file  = cstr dst.realdirpath.to_path
   end
 
-  def render partial, locals: {}
-    return do_render "_#{partial}.erb", locals
+  def render partial, opts = { :locals => {} }
+    return do_render "_#{partial}.erb", opts[:locals]
   end
 
   def generate template
diff --git a/tool/ruby_vm/helpers/scanner.rb b/tool/ruby_vm/helpers/scanner.rb
index 5ae1363480..8f7531abda 100644
--- a/tool/ruby_vm/helpers/scanner.rb
+++ b/tool/ruby_vm/helpers/scanner.rb
@@ -20,7 +20,7 @@ class RubyVM::Scanner
   attr_reader :__LINE__
 
   def initialize path
-    src       = Pathname.new __dir__
+    src       = Pathname.new(__FILE__).realpath.dirname
     src      += path
     @__LINE__ = 1
     @__FILE__ = src.realpath.to_path
diff --git a/tool/ruby_vm/loaders/insns_def.rb b/tool/ruby_vm/loaders/insns_def.rb
index 987e29640a..f83cc77fa1 100644
--- a/tool/ruby_vm/loaders/insns_def.rb
+++ b/tool/ruby_vm/loaders/insns_def.rb
@@ -42,7 +42,7 @@ grammar = %r'
 
 until scanner.eos? do
   next if scanner.scan(/\G#{grammar}\g<ws>+/o)
-  split = -> (v) {
+  split = lambda {|v|
     case v when /\Avoid\z/ then
       []
     else
diff --git a/tool/ruby_vm/models/bare_instructions.rb b/tool/ruby_vm/models/bare_instructions.rb
index a9cb4db953..16d5782e2f 100644
--- a/tool/ruby_vm/models/bare_instructions.rb
+++ b/tool/ruby_vm/models/bare_instructions.rb
@@ -28,7 +28,7 @@ class RubyVM::BareInstructions
     @pops     = typesplit @sig[:pop].reject {|i| i == '...' }
     @rets     = typesplit @sig[:ret].reject {|i| i == '...' }
     @attrs    = opts[:attributes].map {|i|
-      RubyVM::Attribute.new insn: self, **i
+      RubyVM::Attribute.new i.merge(:insn => self)
     }.each_with_object({}) {|a, h|
       h[a.key] = a
     }
@@ -149,8 +149,7 @@ class RubyVM::BareInstructions
   end
 
   @instances = RubyVM::InsnsDef.map {|h|
-    hh = h.merge(:template => h)
-    new hh
+    new h.merge(:template => h)
   }
 
   def self.fetch name
diff --git a/tool/ruby_vm/models/operands_unifications.rb b/tool/ruby_vm/models/operands_unifications.rb
index 2a34ea0f62..184bb7d79c 100644
--- a/tool/ruby_vm/models/operands_unifications.rb
+++ b/tool/ruby_vm/models/operands_unifications.rb
@@ -30,7 +30,7 @@ class RubyVM::OperandsUnifications < RubyVM::BareInstructions
     json[:name]      = parts[:name]
     @preamble        = parts[:preamble]
     @spec            = parts[:spec]
-    super template: template, **json
+    super json.merge(:template => template)
     parts[:vars].each do |v|
       @variables[v[:name]] ||= v
     end