This feels like a faq, but I couldn't find anything related so here
goes.
I'd like to compile in the build time into my application. I have a
recipe like this:
BUILDTIME = $(shell TZ=UTC date --utc)
builddate.c:
echo "#include <builddate.h>" >$@
echo >>$@
echo "const char *BuildDate = \"$(BUILDTIME)\";" >>$@
What I'm having trouble with is getting the builddate.c recipe to happen
at the right time. I don't want to make it .PHONY since I don't want to
re-generate, re-compile, and re-link unless something else has actually
changed.
In Makefile.am I have the above, preceded by:
bin_PROGRAMS = geoidx
geoidx_SOURCES = geoidx.c
nodist_geoidx_SOURCES = builddate.c
This happily gets me builddate.c generated and compiled once, but never
updated.
If I was writing my own makefile, I'd have a recipe like this:
geoidx: $(OBJS)
<generate builddate.c -- the three echo lines from above>
<compile buliddate.c>
<link geoidx with $(OBJS) and builddate.o>
But I'm not sure how to get automake to generate a Makefile like this.
Can someone point me in the right direction, or suggest another approach
to get this done?
Thanks much.
-DB
