Re: [PATCH v1] checkpatch: test missing initial blank line in block comment

[Hugues FRUCHET]

On 04/05/2017 10:35 AM, Joe Perches wrote:
> On Wed, 2017-04-05 at 08:23 +0000, Hugues FRUCHET wrote:
>> Hi Joe, thanks for reviewing,
>
> Hello Hugues
>
>> I have run the command you advice on the entire kernel code, modifying
>> the script to only match the newly introduced check case.
>> There was 14389 hits, quite huge, so I cannot 100% certify that there
>> are no false positives, but I have checked the output carefully and
>> found 2 limit cases:
>>
>> 1) space character placed just after "/*"
>> WARNING: Block comments starts with an empty /*
>> #330: FILE: arch/alpha/kernel/core_irongate.c:330:
>> +	/*
>> +	 * Check for within the AGP aperture...
>> => 146 hits (grep -c -n -E "\/\* $" /tmp/check.txt)
>>
>> 2) // style comment followed by pointer dereference
>> WARNING: Block comments starts with an empty /*
>> #426: FILE: drivers/media/dvb-core/dvb_ca_en50221.c:426:
>> +	// success
>> +	*tupleType = _tupleType;
>> => 4 hits
>>
>> Anyway this reveal comment style related issues, so I would say that we
>> can keep script as it is, what do you think about ?
>
> Glancing at the output, there is also the comment
> in a multiline macro case:
>
> WARNING: Block comments starts with an empty /*
> #354: FILE: arch/mips/include/asm/processor.h:354:
> +	/*							\
> +	 * Other stuff associated with the process		\
>
> Dunno how common that is, but maybe the test
> should be changed to avoid those.
>

Here is a proposal that remove this macro case:

# Missing initial /*
if ($realfile !~ m@^(drivers/net/|net/)@ &&	#networking exception
     $prevrawline =~ /^\+[ \t]\/\**.+[ \t]/ &&	#start with /*...
     $prevrawline !~ /^\+.*\/\*.*\*\/[ \t]*/ &&	#no inline /*...*/
+   $prevrawline !~ /^\+[ \t]\/\*+[ \t]+\\$/ &&#no macro /*<tab><\>
     $rawline =~ /^\+[ \t]*\*/ &&
     $realline > 2) {
	WARN("MISSING_INITIAL_BLOCK_COMMENT_STYLE",
	     "Block comments starts with an empty /*\n" . $hereprev);
}

BR,
Hugues.