Use the drx_print() helper in 3 cases inside code which counts macro
arg expansions.
$ scripts/checkpatch.pl --strict patch-1 --debug rx='##'
drx_print: 'arg ##' catenations
>> Matched (`$&`): <_id##>
drx_print: 'arg ##' catenations
>> Matched (`$&`): <_id##>
drx_print: '#|## arg' catenations
>> Matched (`$&`): <##_model>
drx_print: '#|## arg' catenations
>> Matched (`$&`): <##_model>
$ scripts/checkpatch.pl --strict patch-1 --debug rx='insp'
drx_print: -arg-inspections-
>> Matched (`$&`): <__builtin_constant_p(cls>
>> Capture 1 (`$1`): <__builtin_constant_p>
NB: see also the extended --debug key=1 facility:
$ scripts/checkpatch.pl --strict ../linux.git/pt-1 --debug foo=1
Unknown debug key 'foo', expecting: 'values possible type attr rx'
NB: I moved the 2 #|## strippers above the more complex macro, because
the latter caught one ## case that it needn't have.
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
---
scripts/checkpatch.pl | 14 +++++++++++---
1 file changed, 11 insertions(+), 3 deletions(-)
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index c174e3bef2b2..240ddab17d89 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -6078,9 +6078,17 @@ sub process {
next if ($arg =~ /\.\.\./);
next if ($arg =~ /^type$/i);
my $tmp_stmt = $define_stmt;
- $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;
+
+ $tmp_stmt =~ s/\#+\s*$arg\b/drx_print("'#|## arg' catenations")/ge;
+ $tmp_stmt =~ s/\b$arg\s*\#\#/drx_print("'arg ##' catenations");/ge;
+ $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 }
+ {
+ drx_print("-arg-inspections-");
+ }xge;
+
my $use_cnt = () = $tmp_stmt =~ /\b$arg\b/g;
if ($use_cnt > 1) {
CHK("MACRO_ARG_REUSE",
--
2.51.0On Sun, 2025-10-26 at 14:21 -0600, Jim Cromie wrote:
> Use the drx_print() helper in 3 cases inside code which counts macro
> arg expansions.
[]
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
[]
> @@ -6078,9 +6078,17 @@ sub process {
> next if ($arg =~ /\.\.\./);
> next if ($arg =~ /^type$/i);
> my $tmp_stmt = $define_stmt;
> - $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;
> +
> + $tmp_stmt =~ s/\#+\s*$arg\b/drx_print("'#|## arg' catenations")/ge;
> + $tmp_stmt =~ s/\b$arg\s*\#\#/drx_print("'arg ##' catenations");/ge;
stray trailing ; in the replacement ?
> + $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 }
This might be easier to read using a qr but I'm not sure the
embedded capture groups and their use in drx_print is sensible
as it doesn't seem extensible.
our $stmt_stripper = qr{\b(
__must_be_array |
offsetof | typeof | __typeof__ |
sizeof | sizeof_field |
__builtin\w+
typecheck\s*\(\s*$Type\s*,|\#+)\s*\(*\s*$arg\s*\)\(*\s*$arg\s*\)*
> + {
> + drx_print("-arg-inspections-");
> + }xge;
> +
> my $use_cnt = () = $tmp_stmt =~ /\b$arg\b/g;
> if ($use_cnt > 1) {
> CHK("MACRO_ARG_REUSE",
Back with I suggested this a dozen years ago I thought it was overkill.
Maybe it is and the whole test should be offed.
https://lore.kernel.org/lkml/1352198139.16194.21.camel@joe-AO722/
On Sun, Oct 26, 2025 at 5:40 PM Joe Perches <joe@perches.com> wrote:
>
> On Sun, 2025-10-26 at 14:21 -0600, Jim Cromie wrote:
> > Use the drx_print() helper in 3 cases inside code which counts macro
> > arg expansions.
> []
> > diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> []
> > @@ -6078,9 +6078,17 @@ sub process {
> > next if ($arg =~ /\.\.\./);
> > next if ($arg =~ /^type$/i);
> > my $tmp_stmt = $define_stmt;
> > - $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;
> > +
> > + $tmp_stmt =~ s/\#+\s*$arg\b/drx_print("'#|## arg' catenations")/ge;
> > + $tmp_stmt =~ s/\b$arg\s*\#\#/drx_print("'arg ##' catenations");/ge;
>
> stray trailing ; in the replacement ?
>
> > + $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 }
>
> This might be easier to read using a qr but I'm not sure the
> embedded capture groups and their use in drx_print is sensible
> as it doesn't seem extensible.
>
yes, the extra whitespace is better.
I will play with qr// see if the captures work the same.
> our $stmt_stripper = qr{\b(
> __must_be_array |
> offsetof | typeof | __typeof__ |
> sizeof | sizeof_field |
> __builtin\w+
> typecheck\s*\(\s*$Type\s*,|\#+)\s*\(*\s*$arg\s*\)\(*\s*$arg\s*\)*
>
> > + {
> > + drx_print("-arg-inspections-");
> > + }xge;
> > +
> > my $use_cnt = () = $tmp_stmt =~ /\b$arg\b/g;
> > if ($use_cnt > 1) {
> > CHK("MACRO_ARG_REUSE",
>
> Back with I suggested this a dozen years ago I thought it was overkill.
> Maybe it is and the whole test should be offed.
>
I am now playing with an __lvalue(x) macro,
based upon __must_be_array(x),
it is a compile-time check, so it gives a high-quality signal to checkpatch
if x is an lval, the multiple expansion warnings can be silenced for x.
So if this works out, we could take off the wart, rather than the finger.
> https://lore.kernel.org/lkml/1352198139.16194.21.camel@joe-AO722/
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