From: Xining Xu <[email protected]>
If function-like macros do not utilize a parameter, it might result in a
build warning. In our coding style guidelines, we advocate for utilizing
static inline functions to replace such macros. This patch verifies
compliance with the new rule.
For a macro such as the one below,
#define test(a) do { } while (0)
The test result is as follows.
ERROR: Parameter 'a' is not used in function-like macro, please use static
inline instead
#21: FILE: mm/init-mm.c:20:
+#define test(a) do { } while (0)
total: 1 errors, 0 warnings, 8 lines checked
Signed-off-by: Xining Xu <[email protected]>
Tested-by: Barry Song <[email protected]>
Cc: Chris Zankel <[email protected]>
Cc: Huacai Chen <[email protected]>
Cc: Herbert Xu <[email protected]>
Cc: Guenter Roeck <[email protected]>
Cc: Stephen Rothwell <[email protected]>
Cc: Mark Brown <[email protected]>
Cc: Andy Whitcroft <[email protected]>
Cc: Dwaipayan Ray <[email protected]>
Cc: Joe Perches <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Cc: Lukas Bulwahn <[email protected]>
Cc: Max Filippov <[email protected]>
---
scripts/checkpatch.pl | 30 ++++++++++++++++++++++++++++++
1 file changed, 30 insertions(+)
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 9c4c4a61bc83..bcb886014d60 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -6109,6 +6109,36 @@ sub process {
WARN("TRAILING_SEMICOLON",
"macros should not use a trailing
semicolon\n" . "$herectx");
}
+
+ # match "\s*" rather than "\s+" after the balanced
parens, as macro definition with arguments
+ # is not required to have whitespace after arguments
+ if ($dstat =~
/^\+\s*#\s*define\s+$Ident$balanced_parens\s*(\S+.*)(\/[\/*].*)?/) {
+ my $params = $1 || "";
+ my $body = $2 || "";
+
+ # get the individual params
+ $params =~ tr/()//d;
+ # remove leading and trailing whitespace
+ $params =~ s/^\s+|\s+$//g;
+
+ $ctx =~ s/\n*$//;
+ my $cnt = statement_rawlines($ctx);
+ my $herectx = get_stat_here($linenr, $cnt,
$here);
+
+ if ($params ne "") {
+ my @paramList = split /,\s*/, $params;
+ foreach my $param(@paramList) {
+ if ($param =~ /\.\.\.$/) {
+ # if the param name
ends with "...", skip the check
+ next;
+ }
+ if ($body !~ /\b$param\b/) {
+
WARN("UNUSED_PARAM_IN_MACRO",
+ "Parameter
'$param' is not used in function-like macro\n" . "$herectx");
+ }
+ }
+ }
+ }
}
# check for redundant bracing round if etc
--
2.34.1
