You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: spec_helper.rb
    path of file: ./repos/ruby/spec/ruby/optional/capi
    
    the code of the file until where you have to start completion: # Require the main spec_helper.rb at the end to let `ruby ...spec.rb` work

# MRI magic to use built but not installed ruby
$extmk = false

require 'rbco
    
def setup_make
  make = ENV['MAKE']
  make ||= (RbConfig::CONFIG['host_os'].include?("mswin") ? "nmake" : "make")
  make_flags = ENV["MAKEFLAGS"] || ''

  # suppress logo of nmake.exe to stderr
  if File.basename(make, ".*").downcase == "nmake" and !make_flags.include?("l")
    ENV["MAKEFLAGS"] = "l#{make_flags}"
  end