doc.pdf is the target.
The following rule triggers a regeneration of
doc.refer is updated, but is also happy when
doc.refer does not exist at all:
doc.pdf: doc.mom $(wildcard doc.refer) pdfmom -e -k < $< > $@
However the following pattern rule does not accomplish the same (the PDF is generated correctly, but a rebuild is not triggered when changing
%.pdf: %.mom Makefile $(wildcard %.refer) pdfmom -e -k < $< > $@
I suspect that the
wildcard command is executed before the
% character is expanded. How can I work around this?