checkpatch: add test for assignment at start of line

Kernel style seems to prefer line wrapping an assignment with the
assignment operator on the previous line like:

	<leading tabs>	identifier =
				expression;
over
	<leading tabs>	identifier
				= expression;

somewhere around a 50:1 ratio

$ git grep -P "[^=]=\s*$" -- "*.[ch]" | wc -l
52008
$ git grep -P "^\s+[\*\/\+\|\%\-]?=[^=>]" | wc -l
1161

So add a --strict test for that condition.

Link: http://lkml.kernel.org/r/1522275726.2210.12.camel@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 6 insertions, 0 deletions

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index d2464002bb40..5deee8bd0bae 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -3062,6 +3062,12 @@ sub process {
                         }
                 }
 
+# check for assignments on the start of a line
+                if ($sline =~ /^\+\s+($Assignment)[^=]/) {
+                        CHK("ASSIGNMENT_CONTINUATIONS",
+                            "Assignment operator '$1' should be on the previous line\n" . $hereprev);
+                }
+
 # check for && or || at the start of a line
                 if ($rawline =~ /^\+\s*(&&|\|\|)/) {
                         CHK("LOGICAL_CONTINUATIONS",