Strange Makefile rule

[Peter Senna Tschudin]

On Tue, Aug 20, 2013 at 6:50 PM, Randy Dunlap <rdunlap at infradead.org> wrote:
> On 08/20/13 09:42, Peter Senna Tschudin wrote:
>> I do not have cross compile environment but I'm curious how the
>> Makefile rule works:
>>
>> linux-next]$ cat drivers/net/ethernet/arc/Makefile
>>
>> obj-$(CONFIG_ARC_EMAC) += arc_emac.o
>>
>> There is no file named arc_emac.h and arc_emac.c at
>> drivers/net/ethernet/arc, so what does that line do?
>
> It uses the rule from the previous line in the Makefile.
> Both lines are:
>
> arc_emac-objs := emac_main.o emac_mdio.o
> obj-$(CONFIG_ARC_EMAC) += arc_emac.o
>
>
> Any xyz-objs defines the files to be used to build xyz.o.
>
> Is that clear yet?
Thanks!

>
>
> --
> ~Randy



-- 
Peter