[OE-core] Why do we allow empty -dev/-dbg packages ?

[ChenQi]

On 12/31/2013 05:45 PM, Martin Jansa wrote:
> On Tue, Dec 31, 2013 at 09:49:21AM +0800, ChenQi wrote:
>> Hi All,
>>
>> This might be a dummy question, but it has been puzzling me for some
>> time. So if someone could give me some explanation, that would be really
>> appreciated.
>>
>> In bitbake.conf, we have:
>> ALLOW_EMPTY_${PN}-dev = "1"
>> ALLOW_EMPTY_${PN}-dbg = "1"
>>
>> That means we allow emtpy -dev/-dbg packages. But what are the benefits
>> of these empty -dev/-dbg packages?
> In some cases it's useful to satisfy default dependcencies:
> bitbake.conf:RDEPENDS_${PN}-staticdev = "${PN}-dev (= ${EXTENDPKGV})"
>
> and -dev needs ${PN} even when it's empty in some recipes where all
> files are split into separate packages
> bitbake.conf:RDEPENDS_${PN}-dev = "${PN} (= ${EXTENDPKGV})"
>
> Not sure about -dbg one.
>

Hi Martin,

Thanks for your explanation.

If I understand it right, the above two RDEPENDS are the default for 
most recipes and are expected to be overridden in some special recipes, 
right? For example, if a recipe is separated into several packages, it's 
possible that we need to override the RDEPENDS_${PN}-dev.

Here's another question. If a -dev package is empty, does the default 
RDEPENDS on "${PN}" still make sense?

Best Regards,
Chen Qi