Re: 2.4 Makefile doubts

[suneesh <suneesh@xxxxxxxxxxxxxx>]

Ed Co wrote:

> Hi All,
>  
> (a) The 2.4 kernel's drivers/net/Makefile has 4 lines in the beginning 
> as follows:
>  
> obj-y    :=
> obj-m   :=
> obj-n    :=
> obj-      :=
>  
> Are these lines necessary; they seem to be clearting the variables. 
> What happens if these 4 lines are not present?

These lines are initialising variables to empty string. I think these 
are not necessary.
Check in the 2.6 series, these lines are not there in the Makefile.

>  
> (b) Also the TULIP objects are included in the final object using the 
> following rules
>  
> ifeq ($(CONFIG_TULIP_,y)
>    obj-y += tulip/tulip.o
> endif
>  
> Any reason why the normal rule as shown below is not used
> obj-$(CONFIG_TULIP) += tulip/tulip.o

Both ways are correct. We can use any of the above based on the requirement.
Use the first method if we want to do something like,

ifeq ($(CONFIG_ISDN_PPP),y)
 obj-$(CONFIG_ISDN) += slhc.o
endif

or use the second one if the status check and adding is direct.


Regards

Suneesh


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