In Saxon SA, if an XSLT template contains (2 or more) local parameters but no other instructions in its body, an incorrect optimization is applied. An example of such a template is
This example comes from ISO schematron; the template exists so that it can be overridden in an importing stylesheet with one that actually does something.
Saxon attempts to extract the two xsl:param "instructions" into a global variable, and fails when evaluating this global variable.
Although the problem manifests itself in Saxon-SA only, the fix is in Saxon-B code and will be placed in Subversion.