Error while compiling ruby 1.9 source code

Hi
I got below error while compiling ruby 1.9 source code. Please
give reply about solution of this error.
Error:

rbconfig.rb unchanged
/users/username1/UnoRuby/ruby_1.9_sourcecode/lib/fileutils.rb:1026:in
method_missing': private methodopen’ called for false:FalseClass
(NoMethodError)
from
/users/username1/UnoRuby/ruby_1.9_sourcecode/lib/fileutils.rb:1026:in
rescue in block in touch' from /users/username1/UnoRuby/ruby_1.9_sourcecode/lib/fileutils.rb:1022:inblock in touch’
from
/users/username1/UnoRuby/ruby_1.9_sourcecode/lib/fileutils.rb:1020:in
each' from /users/username1/UnoRuby/ruby_1.9_sourcecode/lib/fileutils.rb:1020:intouch’
from ./mkconfig.rb:188:in `’
make: *** [.rbconfig.time] Error 1