Re: make question (target dependent variable)

[James]

Thanks. This seesm to work as well.

P = pp qq
T = pp rr

CFLAGS = -c
CFLAGS += $(shell [ $(foreach f,$(P),$(filter $(f),$@)) ] && echo -g)

.PHONY: $(T)
all: $(T)
$(T):
        @echo $@ $(CFLAGS)


James

Paul D. Smith wrote:
> %% "James" <hslee@ind.alcatel.com> writes:
>
>   j> P = pp qq
>   j> T = pp rr
>   j> CFLAGS = -c
>   j> ifneq ($(strip $(foreach f,$(P),$(findstring $(f),$@))),)
>   j> CFLAGS += -g
>   j> endif
>
>   j> .PHONY: $(T)
>   j> all: $(T)
>   j> $(T):
>   j>         @echo $@ $(CFLAGS)
>
> Well, you haven't used any target-specific variable settings here so... ??
>
> This makefile is confused.  You cannot have a line like this:
>
>   j> ifneq ($(strip $(foreach f,$(P),$(findstring $(f),$@))),)
>
> and have it make any sense.  The value $@ is an automatic variable: it
> has a value ONLY in the context of running a particular rule, but here
> you're using it in a preprocessor statement (ifneq), which is expanded
> as the makefile is read in... at that time $@ has no value and so it's
> replaced with the empty string.  Thus, your test will never be true as
> it's looking for $(f) in a constant empty string.
>
> Not to mention you don't want to use findstring here, since this:
>
>     $(findstring foo.o,barfoo.o)
>
> will return true (or, really, "foo.o") when you expect it to return
> false (empty).  You should be using filter and/or filter-out here, as
> those test entire words not just substrings.
>
>
> Why don't you just say:
>   P = pp qq
>   T = pp rr
>   CFLAGS = -c
>
>   .PHONY: $(T)
>   all: $(T)
>   $(P): CFLAGS += -g
>   $(T):
>           @echo $@ $(CFLAGS)
>
> That gives a rule for all targets in variable T, and it sets all targets
> in variable P to have a target-specific variable "CFLAGS += -g", which
> is I think what you wanted.
>
> --
> -------------------------------------------------------------------------------
>  Paul D. Smith <psmith@gnu.org>          Find some GNU make tips at:
>  http://www.gnu.org                      http://make.paulandlesley.org
>  "Please remain calm...I may be mad, but I am a professional." --Mad Scientist