dependencies for $(des_headers) to depend only on the source file
desdata.c, not on the executable.
Rev: src/nettle/Makefile.am:1.22
all-local: nettle.html
-EXTRA_DIST = macros.h memxor.h $(des_headers) descore.README nettle.html .bootstrap
+EXTRA_DIST = macros.h memxor.h $(des_headers) descore.README nettle.html \
+ .bootstrap $(des_headers)
# BUILT_SOURCE = $(des_headers)
des_headers = parity.h rotors.h keymap.h
# Generate DES headers.
-$(des_headers): desdata
+$(des_headers): desdata.c
+ $(MAKE) desdata
./desdata $(@F) > $@T
test -s $@T && mv -f $@T $@