Do not try to chown/chgrp when installing unless running
as root. This is done for the same reasons as the patch for 
lib/rubygems/ext/ext_conf_builder.rb in the Ruby port.

Don't have it accidently use gmake, because the makefiles
created can use BSD make extensions.

Index: lib/rake/extensiontask.rb
--- lib/rake/extensiontask.rb.orig
+++ lib/rake/extensiontask.rb
@@ -157,7 +157,9 @@ module Rake
       task "copy:#{@name}:#{platf}:#{ruby_ver}" => [lib_path, tmp_binary_path, "#{tmp_path}/Makefile"] do
         # install in lib for native platform only
         unless for_platform
-          sh "#{make} install target_prefix=", chdir: tmp_path
+          command = "#{make} install target_prefix="
+          command +=  " INSTALL_PROG='/usr/bin/install -c -m 0755'" unless Process.uid == 0
+          sh command, chdir: tmp_path
         end
       end
       # copy binary from temporary location to staging directory
@@ -502,20 +504,7 @@ Java extension should be preferred.
     end
 
     def make
-      unless @make
-        @make =
-          if RUBY_PLATFORM =~ /mswin/ then
-            'nmake'
-          else
-            ENV['MAKE'] || find_make
-          end
-      end
-
-      unless @make
-        raise "Couldn't find a suitable `make` tool. Use `MAKE` env to set an alternative."
-      end
-
-      @make
+      @make ||= ENV['MAKE'] || 'make'
     end
 
     def find_make