Debugger entered--Lisp error: (error "Stack overflow in regexp matcher")
  looking-at("\\(\\(?:\\(xmlns\\)\\|[_[:alpha:]][-._[:alnum:]]*\\)\\(:[_[:alpha:]][-._[:alnum:]]*\\)?\\)[ 
	\n]*=\\(?:[ 
	\n]*\\('[^<'&
\n	]*\\([&
\n	][^<']*\\)?'\\|\"[^<\"&
\n	]*\\([&
\n	][^<\"]*\\)?\"\\)\\(?:\\([ 
	\n]*>\\)\\|\\(?:\\([ 
	\n]*/\\)\\(>\\)?\\)\\|\\([ 
	\n]+\\)\\)\\)?")
  xmltok-scan-attributes()
  xmltok-scan-after-lt()
  xmltok-forward()
  rng-forward()
  rng-do-some-validation-1(rng-validate-while-idle-continue-p)
  rng-do-some-validation(rng-validate-while-idle-continue-p)
  rng-validate-while-idle(#<buffer url25099xa>)
  #[nil "\204