I've got a Makefile with targets like this:
all: a b
a: a_prereqs a_steps
b: b_prereqs b_steps
a
and b
take a while to run and have prerequisites. I'd like both a_prereqs
and b_prereqs
to run first (so that I don't have to wait for a_steps
to complete before discovering that b_steps
will fail.
But I don't want b_prereqs
to run unless I'm running b
.
How can I do this in GNU Make?