Re: [PATCH] scripts: Fallback to KBUILD_OUTPUT if O is not specified

["Wangnan (F)" <wangnan0@huawei.com>]

On 2016/4/8 22:58, Arnaldo Carvalho de Melo wrote:
> Em Fri, Apr 08, 2016 at 11:14:09AM +0200, Thierry Reding escreveu:
>> From: Thierry Reding <treding@nvidia.com>
>>
>> The KBUILD_OUTPUT environment can be used to set the build directory as
>> an alternative to passing the O variable on the command-line. This works
>> with regular kernel builds, so it's surprising if it doesn't work within
>> the tools/scripts directory.
>>
>> Allow KBUILD_OUTPUT if O is not specified on the command-line to avoid
>> any surprises.
> I think this is fine, Jiri, Wang?

The idea is fine, but we should be very careful when touching Makefile
to avoid breaking build-test like this:

  # export KBUILD_OUTPUT=/tmp/xxxxx
  #  ./tests/perf-targz-src-pkg .
    PERF_VERSION = 4.5.g337b7b
  ls: cannot access perf-*.tar.gz: No such file or directory
  tar: -C: Cannot open: No such file or directory
  tar: Error is not recoverable: exiting now
  make: *** /tmp/tmp.q4egWrFd3L/perf*/tools/perf: No such file or 
directory.  Stop

Moreover, in the above case, the output directory should be

  /tmp/xxxxx

or

  /tmp/xxxxx/tools/perf ?

Since kernel build output things to /tmp/xxxxx, I think we'd better
output to /tmp/xxxxx/tools/perf.

Thank you.

> - Arnaldo
>   
>> Signed-off-by: Thierry Reding <treding@nvidia.com>
>> ---
>> Hi Arnaldo,
>>
>> I'm not sure if you're the right person to send this to. There was noone
>> reported by scripts/get_maintainer.pl, but it looks like you ended up
>> applying most of the patches to this file lately, which kinda makes you
>> the de facto maintainer =).
>>
>> Thierry
>>
>>   tools/scripts/Makefile.include | 4 ++++
>>   1 file changed, 4 insertions(+)
>>
>> diff --git a/tools/scripts/Makefile.include b/tools/scripts/Makefile.include
>> index 8abbef164b4e..5467da41dc72 100644
>> --- a/tools/scripts/Makefile.include
>> +++ b/tools/scripts/Makefile.include
>> @@ -8,6 +8,10 @@ ifeq ($(objtree),)
>>   	objtree := $(O)
>>   endif
>>   endif
>> +else
>> +ifneq ($(KBUILD_OUTPUT),)
>> +	OUTPUT := $(KBUILD_OUTPUT)/$(if $(subdir),$(subdir)/)
>> +endif
>>   endif
>>   
>>   # check that the output directory actually exists
>> -- 
>> 2.8.0