Re: [PATCH 1/1] merge_config.sh: ignore unwanted grep errors

[Guillaume Tucker <guillaume.tucker@collabora.com>]

On 02/09/2019 15:32, Jon Hunter wrote:
> 
> On 02/09/2019 15:26, Guillaume Tucker wrote:
>> On 02/09/2019 15:21, Jon Hunter wrote:
>>>
>>> On 02/09/2019 15:14, Guillaume Tucker wrote:
>>>> + Jon Hunter who hit a similar issue
>>>
>>> Thanks for adding me.
>>>
>>>> On 28/08/2019 21:19, Guillaume Tucker wrote:
>>>>> The merge_config.sh script verifies that all the config options have
>>>>> their expected value in the resulting file and prints any issues as
>>>>> warnings.  These checks aren't intended to be treated as errors given
>>>>> the current implementation.  However, since "set -e" was added, if the
>>>>> grep command to look for a config option does not find it the script
>>>>> will then abort prematurely.
>>>>>
>>>>> Handle the case where the grep exit status is non-zero by setting
>>>>> ACTUAL_VAL to an empty string to restore previous functionality.
>>>>>
>>>>> Fixes: cdfca821571d ("merge_config.sh: Check error codes from make")
>>>>> Signed-off-by: Guillaume Tucker <guillaume.tucker@collabora.com>
>>>>> ---
>>>>>  scripts/kconfig/merge_config.sh | 2 +-
>>>>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>>>>
>>>>> diff --git a/scripts/kconfig/merge_config.sh b/scripts/kconfig/merge_config.sh
>>>>> index d924c51d28b7..d673268d414b 100755
>>>>> --- a/scripts/kconfig/merge_config.sh
>>>>> +++ b/scripts/kconfig/merge_config.sh
>>>>> @@ -177,7 +177,7 @@ make KCONFIG_ALLCONFIG=$TMP_FILE $OUTPUT_ARG $ALLTARGET
>>>>>  for CFG in $(sed -n -e "$SED_CONFIG_EXP1" -e "$SED_CONFIG_EXP2" $TMP_FILE); do
>>>>>  
>>>>>  	REQUESTED_VAL=$(grep -w -e "$CFG" $TMP_FILE)
>>>>> -	ACTUAL_VAL=$(grep -w -e "$CFG" "$KCONFIG_CONFIG")
>>>>> +	ACTUAL_VAL=$(grep -w -e "$CFG" "$KCONFIG_CONFIG" || echo)
>>>
>>> Shouldn't this just be 'true' instead of 'echo'?
>>
>> I just explained why I used "echo" on your thread.  Essentially,
>> I think both can be used but "echo" made more sense to me because
>> the script is then using the output string from the command
>> rather than the exit status.
> 
> Yes just saw that. However, I don't think that using 'echo' is
> necessary. The grep command does not output anything and so the variable
> will essentially be an empty string, we just need to ensure that no
> error is returned from the command. In cases such as these I always use
> 'true' in conjunction with grep.

Sure, that makes sense too.  Your solution is arguably a bit
simpler so I agree it would be better to use "true" here.

I can submit a v2 with "true" if that helps, unless you prefer to
send your version of the fix yourself?


Also we're actually using this fix in KernelCI to test it on top
of Mark's patch:

  https://github.com/kernelci/linux/commits/staging.kernelci.org

so I can get it tested again with quite a few build variants
using "true".  It's kind of trivial but we need a working
merge_config.sh anyway on that branch.

Guillaume