Re: RFC: doc for `Handling Tools that Produce Many Outputs'

[Eric Siegerman]

On Thu, Feb 05, 2004 at 10:49:07AM +1100, Robert Collins wrote:
> On Thu, 2004-02-05 at 10:36, Eric Siegerman wrote:
> 
> > I believe this fails on the following corner case.  Suppose the
> > date ordering is like this (with data.h being the oldest):
> >     data.h   data.foo   data.c
> > 
> > data.h is out of date with respect to data.foo, so one wants to
> > rebuild it, but I don't think that will happen:
> 
> 
> Then data.c is not derived from data.foo. Or someone has manually edited
> it - either of which is incorrect for this scenario.

Or, after a build, the right version of data.h somehow got
overwritten with an out-of-date version.  That's a user error
too, of course.

I was well aware that this case "should never occur".  My point
was that (as with any system or component) a Makefile that does
the right thing when handed bad input is to be preferred over one
that doesn't.  How much more important that is, then, for an
officially recommended design pattern, which will (one hopes) be
propagated into a great number of Makefiles!


On Thu, Feb 05, 2004 at 08:25:52AM +0100, Tim Van Holder wrote:
> Wouldn't this help somewhat for a case like this:
>    [example deleted]
> 
> It wouldn't do anything about the contents of the file

Why, then, is it to be preferred over an approach that does?

--

|  | /\
|-_|/  >   Eric Siegerman, Toronto, Ont.        address@hidden
|  |  /
It must be said that they would have sounded better if the singer
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drum kit around during songs.
        - Patrick Lenneau