On 9/1/20 5:37 PM, Joe Perches wrote:
> On Tue, 2020-09-01 at 12:48 +0300, Denis Efremov wrote:
>> uninitialized_var() macro was removed from the sources [1] and
>> other warning-silencing tricks were deprecated [2]. The purpose of this
>> cocci script is to prevent new occurrences of uninitialized_var()
>> open-coded variants.
>
>> +(
>> +* T var =@p var;
>> +|
>> +* T var =@p *(&(var));
>> +|
>> +* var =@p var
>> +|
>> +* var =@p *(&(var))
>> +)
>
> Adding a checkpatch test might be a good thing too.
>
> ---
> scripts/checkpatch.pl | 11 +++
> 1 file changed, 11 insertions(+)
>
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> index 149518d2a6a7..300b2659aab3 100755
> --- a/scripts/checkpatch.pl
> +++ b/scripts/checkpatch.pl
> @@ -3901,6 +3901,17 @@ sub process {
> #ignore lines not being added
> next if ($line =~ /^[^\+]/);
>
> +# check for self assigments used to avoid compiler warnings
> +# e.g.: int foo = foo, *bar = NULL;
> +#struct foo bar = *(&(bar));
> + if ($line =~ /^\+\s*(?:$Declare)?([A-Za-z_][A-Za-z\d_]*)\s*=/) {
> + my $var = $1;
> + if ($line =~
> /^\+\s*(?:$Declare)?$var\s*=\s*(?:$var|\*\s*\(?\s*&\s*\(?\s*$var\s*\)?\s*\)?)\s*[;,]/)
> {
> + WARN("SELF_ASSIGNMENT",
> + "Do not use self-assignments to avoid
> compiler warnings\n" . $herecurr);
> + }
> + }
> +
> # check for dereferences that span multiple lines
> if ($prevline =~ /^\+.*$Lval\s*(?:\.|->)\s*$/ &&
> $line =~ /^\+\s*(?!\#\s*(?!define\s+|if))\s*$Lval/) {
Looks good. I also faced this kind of assignments after declarations.
https://lkml.org/lkml/2020/8/31/85
I'm not sure if they are used to suppress compiler warnings, through.
Denis
