Re: Should this makefile really hang make?

[Bryan Ischo]

On 11/15/11 13:41, Paul Smith wrote:
> On Tue, 2011-11-15 at 13:30 -0800, Bryan Ischo wrote:
> > .SECONDEXPANSION:
> > all: foo.a
> > %.a: $$(@:%.a=%.o)
> An infinite loop is bad, sure; I'll check that out.  But why don't you
> just write:
>
>          all: foo.a
>          %.a: %.o
>
> ??? There's no need for secondary expansion here.

It's just a demonstration of the problem, and the most succinct one I 
could find.

What I am really trying to do is something like this:

all: lib/libfoo.a lib/libfoo.so lib/libbar.a lib/libbar.so

%.o: %.c
      gcc -o %@ -c $^

%.po: %.c
      gcc -fPIC -o %@ -c $^

%.a: $$($$(basename $$(notdir $$@))_COMPONENTS)
      ar crv $@ $^

%.so: $$($$(basename $$(notdir $$@))_COMPONENTS:%.o=%.po)
      gcc -shared -o $@ $^

libfoo_COMPONENTS = foo.o foo2.o

libbar_COMPONENTS = bar.o

I have also tried this to get around the hang:

%.so: $$(patsubst %.o,%.po,$$($$(basename $$(notdir $$@))_COMPONENTS))
      gcc -shared -o $@ $^

But the patsubst doesn't seem to work right; it doesn't substitute anything.

Thanks!
Bryan