Re: [PATCH] scripts: kernel-doc: Ignore __alloc_size() attribute

[Joe Perches <joe@perches.com>]

On Mon, 2021-10-11 at 11:06 -0700, Kees Cook wrote:
> Fixes "Compiler Attributes: add __alloc_size() for better bounds checking"
> so that the __alloc_size() macro is ignored for function prototypes when
> generating kerndoc. Avoids warnings like:
> 
> ./include/linux/slab.h:662: warning: Function parameter or member '1' not described in '__alloc_size'
> ./include/linux/slab.h:662: warning: Function parameter or member '2' not described in '__alloc_size'
> ./include/linux/slab.h:662: warning: expecting prototype for kcalloc().  Prototype was for __alloc_size() instead
[]
> diff --git a/scripts/kernel-doc b/scripts/kernel-doc
[]
> @@ -1789,6 +1789,7 @@ sub dump_function($$) {
>      $prototype =~ s/__weak +//;
>      $prototype =~ s/__sched +//;
>      $prototype =~ s/__printf\s*\(\s*\d*\s*,\s*\d*\s*\) +//;
> +    $prototype =~ s/__alloc_size\s*\(\s*\d+\s*(?:,\s*\d+\s*)?\) +//;
>      my $define = $prototype =~ s/^#\s*define\s+//; #ak added
>      $prototype =~ s/__attribute_const__ +//;
>      $prototype =~ s/__attribute__\s*\(\(

Perhaps all this would be more intelligible and a bit more future-proof
using a regex that consumes all the various __<foo> prefixed attributes.

Maybe:

	my $balanced_parens = qr/(\((?:[^\(\)]++|(?-1))*\))/;
	$prototype =~ s/\b__\w+\s*(?:$balanced_parens)?\s*//g;