Pattern rules without commands, does it make sense?

[Leeuwesteijn,Joost]

Hi *,

>From chapter "Implicit Rule Search Algorithm":
"4. Remove from the list all rules with no commands."

Just to be sure: are pattern rules without commands totally useless?

I expected them to be 'incremental', just like normal rules. Normal rules
also continue when there are no commands. Like so:
-------------------
foo%.o : bar%.c
# no commands here

%.o : %.c
    @(COMPILE_AWAY)
-------------------

Is the first rule useless? I expected (was hoping for):
- if the first rule matches (e.g. foo1.o,bar1.c) -> 
  there's no rule, continue with the matched data because not finished yet
- foo1.o,bar1.c also matches %.o:%.c ->
  this one does have commands -> compile

Instead I get "make: *** No rule to make target" :-(

--
Joost Leeuwesteijn