[Buildroot] [PATCH v2 2/3] package: fix generic extract target for top-level parallel make

[Arnout Vandecappelle <arnout@mind.be>]

On 08/26/13 10:29, Fabio Porcedda wrote:
> On Thu, Aug 22, 2013 at 5:59 PM, Arnout Vandecappelle <arnout@mind.be> wrote:
>> On 22/08/13 09:44, Fabio Porcedda wrote:
[snip]
>>> To be able to change the others targets i need to add stamp file for
>>> every target inside $$($(2)_DEPENDENCIES,
>>> i need to do that because a file cannot depends on a non existing file.
>>
>>
>>   That's not true. Take the following Makefile:
>>
>> ----------------
>> %.source:
>>          touch $@
>>
>> %.extract: %.source
>>          touch $@
>>
>> %.config: %.extract
>>          touch $@
>>
>> %.build: %.config
>>          touch $@
>>
>> X_DEPS = y z
>>
>> x.config: $(X_DEPS)
>
> The problem with this solution is that the "x.config" target is
> reevaluated every time because it does not depends on a virtual
> target, the only solution that i found is to add a stamp file for
> every dependencies.
> Using virtual target as dependency is fine only with virtual targets.

  Ah yes, you're right.

  However, using the order-only rule that you mentioned in reply to 
Thomas solves the problem. So

x.config: | $(X_DEPS)


  Regards,
  Arnout


-- 
Arnout Vandecappelle                          arnout at mind be
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