[U-Boot] [PATCH 1/1] checkpatch.pl: Add warning for new __packed additions

[Heinrich Schuchardt]

While there are valid reasons to use __packed, often the answer is that
you should be doing something else here instead.

This reintroduces the changes of
f503cc49a570 (Add warning for new __packed additions)

Signed-off-by: Heinrich Schuchardt <xypron.glpk at gmx.de>
---
This patch is to go after
[PATCH v2 1/1] checkpatch: update from Linux v4.13-rc6

In the git log I found no other contributions that we loose by
upgrading to the new checkpatch version.

I just wonder if the warning text makes sense.
Wouldn't it be more helpful to write:

"Sequencing structure members in a packed order is
preferable to using __packed."

Maybe this is also the reason why this check was not accepted
by upstream.
---
 scripts/checkpatch.pl | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 2287a0bca8..4142f5c837 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -5616,6 +5616,13 @@ sub process {
 			     "__packed is preferred over __attribute__((packed))\n" . $herecurr);
 		}
 
+# Check for new packed members, warn to use care
+		if ($realfile !~ m@\binclude/uapi/@ &&
+		    $line =~ /\b(__attribute__\s*\(\s*\(.*\bpacked|__packed)\b/) {
+			WARN("NEW_PACKED",
+			     "Adding new packed members is to be done with care\n" . $herecurr);
+		}
+
 # Check for __attribute__ aligned, prefer __aligned
 		if ($realfile !~ m@\binclude/uapi/@ &&
 		    $line =~ /\b__attribute__\s*\(\s*\(.*aligned/) {
-- 
2.11.0