Path: utzoo!attcan!uunet!mcsun!cernvax!chx400!mecazh!paul
From: paul@mecazh.uu.ch (Paul Breslaw)
Newsgroups: comp.sys.hp
Subject: Re^2: GNU Make 3.58 on HP-UX 7.0 ?
Message-ID: <434@node17.mecazh.uu.ch>
Date: 1 Oct 90 19:50:10 GMT
References: <1990Sep17.201337.15659@bpdsun1.uucp> <7370218@hpfcso.HP.COM> <TT.90Sep30092828@euler.jyu.fi>
Organization: Mecasoft SA, Zurich, Switzerland
Lines: 41


Instead of all this political GNU/HP bashing, would anyone mind if
I went back to the original subject of this discussion, namely GNUmake,
and could someone help me with the following observation.

Here is a Makefile

OBJ = foo.o

all:	$(OBJ)
	@echo $(OBJ) up to date

foo.o:	foo.h foo.c
	cc -o foo.o $<


Now 

$ gnumake -n
        cc -o foo.o foo.h         <== observe
        echo foo.o up to date
$ /bin/make -n
        cc -o foo.o foo.c         <== observe
        echo foo.o up to date

The GNUmake documentation defines $< as the name of the *first* dependency.

The HPmake documentation says it is evaluated only for inference rules
(or the .DEFAULT) rule. (Hence the meaningless symbolic target 'all'.
Without it $< doesn't get evaluated at all, and I get cc -o foo.o as output)

Can someone explain why so simple a Makefile is treated so differently
by the two make's. And, if the question is not meaningless, which is
correct?

Paul Breslaw

-- 
Paul Breslaw, Mecasoft SA,          |  telephone :  41 1 362 2040
Guggachstrasse 10, CH-8057 Zurich,  |  e-mail    :  paul@mecazh.uu.ch
Switzerland.                        |               mcsun!chx400!mecazh!paul