[ruby-dev:18577]
* ext/extmk.rb (extmake): expand $srcdir.
* ext/win32ole/extconf.rb: should not override $CFLAGS, but
append.
* lib/mkmf.rb (config_string): use given config hash.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@2991 b2dd03c8-39d4-4d8f-98ff-823fe69b080e