From 9192d41a3f0b98844860f1de5b82f729bbe07c61 Mon Sep 17 00:00:00 2001
From: Joe Perches <joe@perches.com>
Date: Tue, 11 Oct 2016 13:52:11 -0700
Subject: [PATCH] checkpatch: add --strict test for precedence challenged macro
arguments
Add a test for macro arguents that have a non-comma leading or trailing
operator where the argument isn't parenthesized to avoid possible precedence
issues.
Link: http://lkml.kernel.org/r/47715508972f8d786f435e583ff881dbeee3a114.1473745855.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Julia Lawall <julia.lawall@lip6.fr>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
scripts/checkpatch.pl | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index f135f8e4d069..ea1a7adce406 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -4836,7 +4836,7 @@ sub process {
# check if any macro arguments are reused (ignore '...' and 'type')
foreach my $arg (@def_args) {
next if ($arg =~ /\.\.\./);
- next if ($arg =~ /^type$/);
+ next if ($arg =~ /^type$/i);
my $tmp = $define_stmt;
$tmp =~ s/\b(typeof|__typeof__|__builtin\w+|typecheck\s*\(\s*$Type\s*,|\#+)\s*\(*\s*$arg\s*\)*\b//g;
$tmp =~ s/\#\s*$arg\b//g;
@@ -4845,6 +4845,13 @@ sub process {
if ($use_cnt > 1) {
CHK("MACRO_ARG_REUSE",
"Macro argument reuse '$arg' - possible side-effects?\n" . "$herectx");
+ }
+# check if any macro arguments may have other precedence issues
+ if ($define_stmt =~ m/($Operators)?\s*\b$arg\b\s*($Operators)?/m &&
+ ((defined($1) && $1 ne ',') ||
+ (defined($2) && $2 ne ','))) {
+ CHK("MACRO_ARG_PRECEDENCE",
+ "Macro argument '$arg' may be better as '($arg)' to avoid precedence issues\n" . "$herectx");
}
}