Re: [dpdk-dev] [PATCH v8 1/2] mk:Simplify the ifdefs in rte.app.mk

[Olivier MATZ <olivier.matz@6wind.com>]

On 05/13/2015 04:04 PM, Wiles, Keith wrote:
>
>
> On 5/13/15, 8:56 AM, "Olivier MATZ" <olivier.matz@6wind.com> wrote:
>
>> Hi Keith,
>>
>> On 05/13/2015 03:17 PM, Wiles, Keith wrote:
>>>>>
>>>>>     endif # ifeq ($(NO_AUTOLIBS),)
>>>>>
>>>>> -LDLIBS += $(CPU_LDLIBS)
>>>>> +LDLIBS += $(_LDLIBS-y) $(EXTRA_LDLIBS)
>>>>>
>>>>
>>>> As discussed in the previous mail, all things that are about
>>>> EXTRA_LDLIBS should be moved in the second patch. Therefore,
>>>> the title of the second patch should not be "update doc...", but
>>>> something like "mk: introduce EXTRA_LDLIBS...".
>>>>
>>>> By the way, I missed that before, but it seems that your
>>>> patch removes CPU_LDLIBS, I don't think it's correct.
>>>
>>> I found no reference to CPU_LDLIBS in the docs or code other then then
>>> one
>>> line. We now have EXTRA_LDLIBS for the command line, right?
>>
>> Yes, but your patch says "simplify the ifdef". Removing
>> a variable (even if it is not used) in this patch is not
>> a good idea.
>>
>> Now, the CPU_CFLAGS, CPU_LDFLAGS, CPU_LDLIBS can be defined internally
>> by the rte.vars.mk in mk/arch/ or mk/machine/ directories.
>
> No docs for CPU_LDLIBS or reference to that variable, which means it does
> not exist, right?
> If it was used or documented then I would agree. Having magic variables is
> not a good idea. I will add the CPU_LDLIBS in to the line, but someone
> will have to document that variable.

First, this variable is internal to DPDK framework. It is not
documented, because the goal of the documentation is not to
document all internal variables. In one word, it's not a magic
variable at all, it is simply a variable.

Now, the heart of the matter is that your patch silently remove
this line. This is not acceptable and that's why I'm commenting
on it. The goal of patch splitting and proper title is to separate
features, and win time when searching in the git log for the cause
of a problem.

This is the same problem with EXTRA_LDLIBS. How can you justify
having 2 patches:
- "simplify the ifdef" that also adds the EXTRA_LDLIBS
  then
- "update the documentation for EXTRA_LDLIBS"

Regards,
Olivier



>>
>> Regards,
>> Olivier
>>
>