c++ will have internal error. Could you check it out? Error: {"code":"InternalError","message":"Invalid regular expression: /^/root/docsets/feeds-master/C++.do

c++ will have internal error. Could you check it out? Error: {"code":"InternalError","message":"Invalid regular expression: /^/root/docsets/feeds-master/C++.docset/Contents/Resources/Documents/?.*/: Nothing to repeat"}