Fix crash on listing when nested noexpand macros are used Macros flagged noexpand were causing a segfault during listing. The problem was incorrect accounting for nesting levels for noexpand macros causing the listing handler to fall off the end of the program in certain circumstances and in other circumstances it would fail to suppress expansion. Both the segfault in the case of misbehaviour and the misbhaviour itself are corrected with this update. If you do not use nested noexpand macros, this bug has no effect.

all:
	hg rm manual/* || true
	rm -f manual/*.pdf manual/*.html
	docbook2html -o manual manual.docbook.sgml
	docbook2html -u manual.docbook.sgml && mv manual.docbook.html manual/manual.html
	docbook2pdf -u manual.docbook.sgml && mv manual.docbook.pdf manual/manual.pdf
	rm -f manual.docbook.html
	hg add manual/*