+ checkpatch-exclude-forward-declarations-of-const-structs.patch added to mm-nonmm-unstable branch

+ checkpatch-exclude-forward-declarations-of-const-structs.patch added to mm-nonmm-unstable branch

[Andrew Morton]

The patch titled
     Subject: checkpatch: exclude forward declarations of const structs
has been added to the -mm mm-nonmm-unstable branch.  Its filename is
     checkpatch-exclude-forward-declarations-of-const-structs.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/checkpatch-exclude-forward-declarations-of-const-structs.patch

This patch will later appear in the mm-nonmm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Taylor Nelms <tknelms@google.com>
Subject: checkpatch: exclude forward declarations of const structs
Date: Tue, 31 Mar 2026 14:15:09 -0400

Limit checkpatch warnings for normally-const structs by excluding patterns
consistent with forward declarations.

For example, the forward declaration `struct regmap_access_table;` in a
header file currently generates a warning recommending that it is
generally declared as const; however, this would apply a useless type
qualifier in the empty declaration `const struct regmap_access_table;`,
and subsequently generate compiler warnings.

Link: https://lkml.kernel.org/r/20260331181509.1258693-1-tknelms@google.com
Signed-off-by: Taylor Nelms <tknelms@google.com>
Acked-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 scripts/checkpatch.pl |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/scripts/checkpatch.pl~checkpatch-exclude-forward-declarations-of-const-structs
+++ a/scripts/checkpatch.pl
@@ -7512,10 +7512,10 @@ sub process {
 		}
 
 # check for various structs that are normally const (ops, kgdb, device_tree)
-# and avoid what seem like struct definitions 'struct foo {'
+# and avoid what seem like struct definitions 'struct foo {' or forward declarations 'struct foo;'
 		if (defined($const_structs) &&
 		    $line !~ /\bconst\b/ &&
-		    $line =~ /\bstruct\s+($const_structs)\b(?!\s*\{)/) {
+		    $line =~ /\bstruct\s+($const_structs)\b(?!\s*[\{;])/) {
 			WARN("CONST_STRUCT",
 			     "struct $1 should normally be const\n" . $herecurr);
 		}
_

Patches currently in -mm which might be from tknelms@google.com are

checkpatch-exclude-forward-declarations-of-const-structs.patch