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> --- Begin Message ---
>
>
>
> Subject: 
>
> Re: gmake $(eval()) question.
>
>
>
>
> Date: 
>
> Fri, 29 Jun 2007 00:38:23 +0200
>
>
>
>
> User-agent: 
>
> Gnus/5.1008 (Gnus v5.10.8) Emacs/22.1.50 (gnu/linux)
>
>
>
>
> address@hidden writes:
>
> > Hi,
> >
> > I have the following Makefile which demonstrates my problem:
> >
> > ---------Begin Makefile------------
> > HI=$(eval HELLO=Hello)
> >
> > all:server client
> >
> > server:
> > <tab>@echo "HELLO: $(HELLO)"
> > <tab>@echo "HI: $(HI)"
> >
> > client:
> > <tab>@echo "HELLO: $(HELLO)"
> > <tab>@echo "HI: $(HI)"
> > -----------End Makefile------------
> >
> > If I run gmake, I get this output:
> > HELLO:
> > HI:
> > HELLO: Hello
> > HI:
> >
> > This thing that puzzles me is why the first line only contains
> > "HELLO:".  As per my understanding, it should be the same as line 3.
>
> This is not possible. When it execute the first echo "HELLO:
> $(HELLO)", $(HI) has not been evaluated yet, so HELLO is not a
> variable defined yet.
>
>
> > If I run "gmake server" or "gmake client", I get:
> > HELLO:
> > HI:
> >
> > Again, I think the first line of output should be "HELLO: Hello"
>
> Impossible, as above.
>
>
> > So can anyone explain why this is happening?  I am running gmake 3.81
> > on Fedora Core 6.
>
> info gmake
>
> = is a textual definition. You can substitute all occurence of HI with
> $(eval HELLO=Hello).  Your makefile is equivalent to:
>
>
> ---------Begin Makefile------------
>
>
> all:server client
>
> server:
>     @echo "HELLO: $(HELLO)"
>     @echo "HI: $(eval HELLO=Hello)"
>
> client:
>     @echo "HELLO: $(HELLO)"
>     @echo "HI: $(eval HELLO=Hello)"
> -----------End Makefile------------
>
> So you see, there's no variable named HELLO defined before you execute
> one of the echo HI lines.
>
>
> In info gmake, you should be able to read about := which may do what you want.
>
> -- 
> __Pascal Bourguignon__                     http://www.informatimago.com/
>
> NOTE: The most fundamental particles in this product are held
> together by a "gluing" force about which little is currently known
> and whose adhesive power can therefore not be permanently
> guaranteed.
>
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