make "quickworld"? (like in DragonFly)

[John Baldwin]

On Monday 30 August 2004 03:27 pm, Tom Alsberg wrote:
> On Sun, Aug 15, 2004 at 09:53:30AM -0700, Brooks Davis wrote:
> > On Sat, Aug 14, 2004 at 10:03:37AM +0200, Geert Hendrickx wrote:
> > > Does adding "NOCLEAN=true" to /etc/make.conf have the same effect?
>
> Just my two cents:
> > Yes, but it's likely to attract flames because NOCLEAN does fail.  If
> > you forget it's in your make.conf there's a good chance you could report
> > a bug that isn't a bug a waste a bunch of developer time.
>
> In that case, there is a bug though - namely, a bug in the Makefile.
> Although this has happened to me in the past, it shouldn't happen in
> normal circumstances.  The idea of Makefiles, when writing them
> correctly, is that only what's affected by a change -- but everything
> affected by it -- will be rebuilt in case of a change.
>
> So there's no good reason for a make to fail unless something very odd
> happened (with the timestamps, etc.) or something like this happens,
> it means some dependency is missing, or some script external to the
> Makefile did something wrong.

That may be true for simple projects but this isn't a simple project.  For 
example, when gcc was recently upgraded it changed the ABI for C++.  Imagine 
if one had mismatched .o files for libstdc++ if some of the source files 
didn't change.  That kind of dependency (on a compiler ABI) is not easily 
expressed in Makefilesm, and certainly not cleanly.

-- 
John Baldwin <jhb at FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve"  =  http://www.FreeBSD.org