error while compiling ruby 1.9 source code

[Chirag Mistry]

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 method `open' 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:in
`block 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:in
`touch'
from ./mkconfig.rb:188:in `<main>'
make: *** [.rbconfig.time] Error 1