Issue #4145 has been updated by Yui NARUSE. Status changed from Open to Assigned Assigned to set to Yui NARUSE Strings encoded in UTF-16 don't support concatenation. Use UTF-16BE or UTF-16LE for processing. I'm considering to warn concatenation of strings encoded in dummy encoding. ---------------------------------------- http://redmine.ruby-lang.org/issues/show/4145 ---------------------------------------- http://redmine.ruby-lang.org