[RFC] scripts: kernel-doc: fix attribute capture in function parsing

[Aditya Srivastava]

Currently, kernel-doc warns for function prototype parsing on the
presence of additional attributes in the definition.

E.g., running kernel-doc -none on include/rdma/iw_cm.h causes this
warning:
"warning: cannot understand function prototype: 'const char *__attribute_const__ iwcm_reject_msg(int reason); '"

Here, the prototype parsing does not take into account the presence
of attribute, "__attribute_const__" before function name.

Provide a simple fix by adding "__attribute_const__" in the corresponding
regex expression.

A quick evaluation by running 'kernel-doc -none' on kernel-tree reveals
that no additional warning or error has been added or removed by the fix.

Suggested-by: Lukas Bulwahn <lukas.bulwahn@xxxxxxxxx>
Signed-off-by: Aditya Srivastava <yashsri421@xxxxxxxxx>
---
 scripts/kernel-doc | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/scripts/kernel-doc b/scripts/kernel-doc
index 68df17877384..8673dc783309 100755
--- a/scripts/kernel-doc
+++ b/scripts/kernel-doc
@@ -1753,6 +1753,7 @@ sub dump_function($$) {
     my $prototype = shift;
     my $file = shift;
     my $noret = 0;
+    my $attribute_const = qr{__attribute_const__};
 
     print_lineno($new_start_line);
 
@@ -1808,7 +1809,7 @@ sub dump_function($$) {
 	$prototype =~ m/^(\w+)\s+([a-zA-Z0-9_~:]+)\s*\(([^\(]*)\)/ ||
 	$prototype =~ m/^(\w+\s*\*+)\s*([a-zA-Z0-9_~:]+)\s*\(([^\(]*)\)/ ||
 	$prototype =~ m/^(\w+\s+\w+)\s+([a-zA-Z0-9_~:]+)\s*\(([^\(]*)\)/ ||
-	$prototype =~ m/^(\w+\s+\w+\s*\*+)\s*([a-zA-Z0-9_~:]+)\s*\(([^\(]*)\)/ ||
+	$prototype =~ m/^(\w+\s+\w+\s*\*+$attribute_const?)\s*([a-zA-Z0-9_~:]+)\s*\(([^\(]*)\)/ ||
 	$prototype =~ m/^(\w+\s+\w+\s+\w+)\s+([a-zA-Z0-9_~:]+)\s*\(([^\(]*)\)/ ||
 	$prototype =~ m/^(\w+\s+\w+\s+\w+\s*\*+)\s*([a-zA-Z0-9_~:]+)\s*\(([^\(]*)\)/ ||
 	$prototype =~ m/^()([a-zA-Z0-9_~:]+)\s*\(([^\{]*)\)/ ||
-- 
2.17.1