I don't know why the behavior here changed, because I don't see any changes
that would cause the problem, but at least the new version makes equal
sense.
for f in $(module_sources); do \
destdir=`dirname $$f` ;\
mkdir -p $$destdir ;\
- if test "$(top_srcdir)/$$f" -nt "$(top_builddir)/$$f" ; then \
+ if test ! -e "$(top_builddir)/$$f" || \
+ test "$(top_srcdir)/$$f" -nt "$(top_builddir)/$$f" ; then \
cp $(top_srcdir)/$$f $$destdir ; \
echo cp $(top_srcdir)/$$f $$destdir ; \
fi ; \