- -rm -f $@ $@.tmp
- $(MAKE) $(AM_MAKEFLAGS) src/bison
- $(top_builddir)/src/bison --help | perl $(CROSS_OPTIONS_PL) >$@.tmp
+ mv -f $@ $@~ || : >$@~
+ -rm -f $@.tmp
+ $(MAKE) $(AM_MAKEFLAGS) src/bison$(EXEEXT)
+ $(top_builddir)/src/bison --help | \
+ perl $(CROSS_OPTIONS_PL) $(top_srcdir)/src/scan-gram.l >$@.tmp
+ diff -u $@~ $@.tmp || true