checkpatch: exclude four preprocessor sub-expressions from MACRO_ARG_REUSE

__must_be_array, offsetof, sizeof_field and __stringify are all
preprocessor macros and do not evaluate their arguments.  As such, it is
safe not to warn when arguments are being reused in those four
sub-expressions.

Exclude those so that they can pass checkpatch.

Link: https://lkml.kernel.org/r/20210407105042.25380-1-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Acked-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 3870c8a0198770ec7637174b2cb4c2aa0a403608..44b9dc330ac6dfcffc2ffddcdd24b5b4a3d792c9 100755 (executable)
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -5829,7 +5829,7 @@ sub process {
                                next if ($arg =~ /\.\.\./);
                                next if ($arg =~ /^type$/i);
                                my $tmp_stmt = $define_stmt;
-                               $tmp_stmt =~ s/\b(sizeof|typeof|__typeof__|__builtin\w+|typecheck\s*\(\s*$Type\s*,|\#+)\s*\(*\s*$arg\s*\)*\b//g;
+                               $tmp_stmt =~ s/\b(__must_be_array|offsetof|sizeof|sizeof_field|__stringify|typeof|__typeof__|__builtin\w+|typecheck\s*\(\s*$Type\s*,|\#+)\s*\(*\s*$arg\s*\)*\b//g;
                                $tmp_stmt =~ s/\#+\s*$arg\b//g;
                                $tmp_stmt =~ s/\b$arg\s*\#\#//g;
                                my $use_cnt = () = $tmp_stmt =~ /\b$arg\b/g;