[dpdk-dev] [PATCH] kni: fix use of undefined comma variable in makefile

[Olivier Matz]

Hi Ferruh,

On 05/30/2016 05:49 PM, Ferruh Yigit wrote:
> On 5/30/2016 12:56 PM, Olivier Matz wrote:
>> The $(comma) variable is not defined in this Makefile, nor in
>> any included Makefile. Seen while doing a "make clean" on ubuntu:
>>
>>   $ make clean
>>   == Clean lib
>>   == Clean lib/librte_compat
>>   == Clean lib/librte_eal
>>   == Clean lib/librte_eal/common
>>   == Clean lib/librte_eal/linuxapp
>>   == Clean lib/librte_eal/linuxapp/eal
>>   == Clean lib/librte_eal/linuxapp/igb_uio
>>   == Clean lib/librte_eal/linuxapp/kni
>>   tr: missing operand after ‘.-’
>>   Two strings must be given when translating.
>>   Try 'tr --help' for more information.
> 
> I don't observe this error on Ubuntu.
> 
> Also did a quick check and $(comma) seems defined, but not sure exactly
> where. What I test:
> 
> $ lsb_release -si
> Ubuntu
> 
> 
> $ git diff
> diff --git a/lib/librte_eal/linuxapp/kni/Makefile
> b/lib/librte_eal/linuxapp/kni/Makefile
> index ac99d3f..dcad241 100644
> --- a/lib/librte_eal/linuxapp/kni/Makefile
> +++ b/lib/librte_eal/linuxapp/kni/Makefile
> @@ -90,4 +90,7 @@ SRCS-y += kni_net.c
>  SRCS-y += kni_ethtool.c
>  SRCS-$(CONFIG_RTE_KNI_VHOST) += kni_vhost.c
> 
> +test_comma:
> +       @echo "= comma: $(comma) ="
> +
> 
> 
> 
> $ make -C lib/librte_eal/linuxapp/kni test_comma
> make: Entering directory '.../dpdk/lib/librte_eal/linuxapp/kni'
> = comma: , =
> make: Leaving directory '.../dpdk/lib/librte_eal/linuxapp/kni'

Thanks for testing and review.
I added the following lines to the makefile (just after the include
rte.vars.mk):

	$(info ------------------)
	$(info comma=$(comma))
	$(info $(origin comma))

And it gives me:

	$ make clean
	== Clean lib/librte_eal/linuxapp/kni
	--------------------
	comma=,
	file
	make -C /lib/modules/3.13.0-79-generic/build
M=/home/user/dpdk.org/build/build/lib/librte_eal/linuxapp/kni
O=/lib/modules/3.13.0-79-generic/build clean
	make -C /usr/src/linux-headers-3.13.0-79-generic \
        KBUILD_SRC=/usr/src/linux-headers-3.13.0-79-generic \

KBUILD_EXTMOD="/home/user/dpdk.org/build/build/lib/librte_eal/linuxapp/kni"
-f /usr/src/linux-headers-3.13.0-79-generic/Makefile \
	        clean
	make -f /usr/src/linux-headers-3.13.0-79-generic/scripts/Makefile.clean
obj=/home/user/dpdk.org/build/build/lib/librte_eal/linuxapp/kni
	--------------------
	comma=
	undefined
	tr: missing operand after ‘.-’
	Two strings must be given when translating.
	Try 'tr --help' for more information.
	[...]

Actually this Makefile is used twice, and second time the $(comma)
variable is not defined.

It seems the $(comma) variable is defined in rte.cpuflags.mk when
including rte.vars.mk:

  mk/rte.vars.mk
    mk/target/generic/rte.vars.mk
      mk/rte.cpuflags.mk    (only if KERNELRELEASE is unset, which is
                             not the case for the second call)


Do you see the issue when you do a "make clean"?

Thanks,
Olivier