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From: Paul Eggleton <paul.eggleton@linux.intel.com>
Date: Wed, 18 Jun 2014 16:50:32 +0100
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Cc: bitbake-devel@lists.openembedded.org
Subject: Re: curious about setting of PROVIDES in bitbake.conf
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On Wednesday 18 June 2014 09:10:00 Robert P. J. Day wrote:
>   from current bitbake.conf file:
> 
> PROVIDES = ""
> PROVIDES_prepend = "${PN} "
> 
> is there a reason that PROVIDES is set to null, only to immediately
> set it based on the following line? is there some subtle issue this is
> meant to address?

I think the intention is to set the initial value to blank, and ensure that 
${PN} is the first item in the list (since _prepend gets applied later). If you 
just simply had PROVIDES = "${PN}" then it could be overridden somewhere else 
such that ${PN} was not in PROVIDES at all, which would be counter-intuitive.

Cheers,
Paul

-- 

Paul Eggleton
Intel Open Source Technology Centre