backtrace:
In /opt/gnucash/share/gnucash/scm/report.scm:
      ...
       165: 8257  (let ((options #)) (gnc:register-option options stylesheet) ...)
        165: 8258* [options-gen]
	In /home/flavio/.gnucash/saved-reports-2.0:
	   5: 8259  (let ((options #)) (let (#) (# option)) options)
	      5: 8260* [gnc:report-template-new-options/name "Cash Flow"]
	      In /opt/gnucash/share/gnucash/scm/report.scm:
	       125: 8261  (let ((templ #)) (if templ (gnc:report-template-new-options
	       templ) #f))
	       In unknown file:
	             ...
		        ?: 8262  [gnc:report-template-new-options #]
			In /opt/gnucash/share/gnucash/scm/report.scm:
			 144: 8263  (let (# # #) (if # # #))
			  151: 8264* [gnc:make-multichoice-option "General" "Stylesheet" ... ...
			   155: 8265* [map #<procedure #f (ss)> ...
			    162: 8266* [gnc:get-html-style-sheets]
			    In /opt/gnucash/share/gnucash/scm/html-style-sheet.scm:
			     268: 8267  (let ((ss #)) (hash-for-each (lambda # #)
			     *gnc:_style-sheets_*) ...)
			      271: 8268  [sort (# # #) #<procedure #f (a b)>]
			      In unknown file:
			         ?: 8269* [#<procedure #f #> # #]
				 In /opt/gnucash/share/gnucash/scm/html-style-sheet.scm:
				  273: 8270* [string<? ...
				   273: 8271* [gnc:html-style-sheet-name #]
				   In unknown file:
				      ?: 8272  (and (eq? (quote #) (record-type-descriptor obj))
				      (struct-ref obj 0))
				         ?: 8273* [eq? #<record-type <html-style-sheet>> ...
					    ?: 8274* [record-type-descriptor #]
					       ?: 8275  (if (struct? obj) (struct-vtable obj) (error (quote
					       not-a-record) obj))
					          ?: 8276* (struct? obj)

						  <unnamed port>: In expression (struct? obj):
						  <unnamed port>: Stack overflow
