Re: Bug or correct behavior?

[Derek Clegg]

On Feb 5, 2008, at 11:45 AM, Mike Shal wrote:

> Pattern rules are treated a little differently. Specifically, see
> section 10.5.1 "Introduction to Pattern Rules" in the make info pages:
>
>  The order in which pattern rules appear in the makefile is important
>  since this is the order in which they are considered.  Of equally
>  applicable rules, only the first one found is used.
>
> In your example, only the first pattern rule will apply, and the foo.h
> dependency will be ignored.

I'm not sure this is correct. If it were, as you point out:

> You could move foo.h to the line above and have a single pattern  
> rule to get your expected behavior in this case.

I tried this, and the behavior is unchanged.  Unless there's a bug,  
this implies that I have a single pattern rule:
  dir/%.c: %.c | dir ; cp $< $@

The rule
  dir/%.c: foo.h

does not appear to be treated as a pattern rule.  (Otherwise, putting  
it first would have changed the behavior.)

Derek