ac/ax_docbook.m4 has the following broken code: for i in /usr/share/xml/docbook/stylesheet/xsl/nwalsh /usr/share/xml/docbook/stylesheet/nwalsh `ls -d /usr/share/{sg,x}ml/docbook/xsl-stylesheets* 2> /dev/null`; do which causes this to trigger, AC_MSG_ERROR([DocBook XSL stylesheets are required for building.]) The correct line of code should be for i in /usr/share/xml/docbook/stylesheet/xsl/nwalsh /usr/share/xml/docbook/stylesheet/nwalsh /usr/share/sgml/docbook/xsl-stylesheets* /usr/share/xml/docbook/xsl-stylesheets*; do The {a,b} syntax is a non-posix extension, and i have no idea what they wanted to accomplish with the ls but that should work if you still want to leave that in.
Created attachment 486472 [details, diff] ac/ax_docbook non-posix ls patch
Thanks, Mikael, Reported upstream as well - https://github.com/mbunkus/mkvtoolnix/issues/2054
Added -r1 in tree, Moritz fixed upstream as well
