1 files changed, 6 insertions, 2 deletions
diff --git a/lib/rubygems/ext/rake_builder.rb b/lib/rubygems/ext/rake_builder.rb
index 0c64e611a0..3b45ef4369 100644
--- a/lib/rubygems/ext/rake_builder.rb
+++ b/lib/rubygems/ext/rake_builder.rb
@@ -5,17 +5,21 @@
 #++
 
 require 'rubygems/ext/builder'
+require 'rubygems/command'
 
 class Gem::Ext::RakeBuilder < Gem::Ext::Builder
 
   def self.build(extension, directory, dest_path, results)
     if File.basename(extension) =~ /mkrf_conf/i then
       cmd = "#{Gem.ruby} #{File.basename extension}"
-      cmd << " #{ARGV.join " "}" unless ARGV.empty?
+      cmd << " #{Gem::Command.build_args.join " "}" unless Gem::Command.build_args.empty?
       run cmd, results
     end
 
-    cmd = ENV['rake'] || 'rake'
+    # Deal with possible spaces in the path, e.g. C:/Program Files
+    dest_path = '"' + dest_path + '"' if dest_path.include?(' ')
+
+    cmd = ENV['rake'] || "#{Gem.ruby} -rubygems #{Gem.bin_path('rake')}" rescue Gem.default_exec_format % 'rake'
     cmd += " RUBYARCHDIR=#{dest_path} RUBYLIBDIR=#{dest_path}" # ENV is frozen
 
     run cmd, results