Re: False positive in checkpatch

[Andy Whitcroft <apw@canonical.com>]

On Tue, Sep 24, 2013 at 07:03:05AM -0700, Paul E. McKenney wrote:
> On Mon, Sep 23, 2013 at 09:21:07PM -0700, Joe Perches wrote:
> > On Mon, 2013-09-23 at 15:59 -0700, Paul E. McKenney wrote:
> > > Hello!
> > > 
> > > The checkpatch.pl script complains as follows:
> > > 
> > > ERROR: need consistent spacing around '*' (ctx:WxB)
> > > #57: FILE: include/linux/rcupdate.h:564:
> > > +		ACCESS_ONCE(p) = (typeof(*(v)) __force space *)(v); \
> > > 
> > > Of course, the two uses of '*' are doing different things, so it should
> > > be OK for the spacing to be different.
> > > 
> > > Could you please fix this?
> > > 
> > > 							Thanx, Paul
> > > 
> > 
> > Hi Paul.
> > 
> > Try this patch: https://lkml.org/lkml/2013/9/2/428
> > 
> > Andy?  Can you verify this suggested patch please?
> 
> That does it, thank you!  And it does look like this patch was directed
> precisely at this patch.  ;-)
> 
> 							Thanx, Paul
> 

How about this one, it is a bit of a hack but does at least correctly
correct the formal characterisation of the operator to unary.

Working on getting this tested a bit better before sending it out
formally.

-apw


>From 5b4e22c123b3492838d12181129a8c168598dbf4 Mon Sep 17 00:00:00 2001
From: Andy Whitcroft <apw@canonical.com>
Date: Tue, 24 Sep 2013 16:10:46 +0100
Subject: [PATCH] checkpatch: handle miss identified binary operators which
 bump a close parenthesis

When we hit a close parenthesis, any binary operators we have without right
hand sides cannot actually be binary if the code is correctly formatted.
Go back and fix up any we get wrong.

Signed-off-by: Andy Whitcroft <apw@canonical.com>
---
 scripts/checkpatch.pl | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 47016c3..3d56e6e 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -1277,6 +1277,16 @@ sub annotate_values {
 			} else {
 				print "PAREN('$1')\n" if ($dbg_values > 1);
 			}
+			# Check for any pending binary operators, if they but up against this
+			# bracket then they are really unary, correct them.
+			my $pos = length($res) - 1;
+			while ($pos >= 0 && substr($res, $pos, 1) eq 'N') {
+				if (substr($var, $pos, 1) eq 'B') {
+					substr($var, $pos, 1) = 'U';
+					print "BINARY WACKED TO UNARY at $pos\n" if ($dbg_values > 1);
+				}
+				$pos--;
+			}
 
 		} elsif ($cur =~ /^($Ident)\s*\(/o) {
 			print "FUNC($1)\n" if ($dbg_values > 1);
@@ -1331,12 +1341,12 @@ sub annotate_values {
 		} elsif ($cur =~ /^(-(?![->])|\+(?!\+)|\*|\&\&|\&)/o) {
 			my $variant;
 
-			print "OPV($1)\n" if ($dbg_values > 1);
 			if ($type eq 'V') {
 				$variant = 'B';
 			} else {
 				$variant = 'U';
 			}
+			print "OPV($1) -> $variant\n" if ($dbg_values > 1);
 
 			substr($var, length($res), 1, $variant);
 			$type = 'N';
-- 
1.8.1.2