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Re: GCC vs. `make' on Solaris


On Sun, May 13, 2001 at 07:10:48PM -0400, Andrew Pimlott wrote:
> On Fri, May 11, 2001 at 11:44:36PM -0300, Alexandre Oliva wrote:
> > But what we generally have is:
> > 
> > foo.o: foo.c
> >         gcc -c foo.c
> > foo.c: s-foo; @true
> > s-foo: bar
> >         bar > tmp-foo
> >         move-if-change tmp-foo foo.c
> >         touch s-foo
> > 
> > Even if foo.c is older than s-foo, GNU make is smart enough to figure
> > @true hasn't changed it, so it doesn't proceed to rebuilding foo.o.
> 
> (While I'm on this thread ...)
> 
> What is the point of the middle rule and s-foo?

It prevents foo.c from being regenerated every time you run make.
Some of the generators are slow, so this is important -
e.g. genattrtab takes almost a minute on my 500MHz Pentium III.

-- 
zw   Actually, we have scientifically determined that Heisenberg did indeed
     sleep exactly here. However, we have no idea whatsoever just how fast
     asleep he was.
     	-- Dave Aronson


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