From 11ca40a0f8e3a788a987f14cb80d836a34d109ae Mon Sep 17 00:00:00 2001 From: Joe Perches Date: Mon, 12 Dec 2016 16:46:31 -0800 Subject: [PATCH] checkpatch: avoid multiple line dereferences Code that puts a single dereferencing identifier on multiple lines like: struct_identifier->member[index]. member = ; is generally hard to follow. Prefer that dereferencing identifiers be single line. Link: http://lkml.kernel.org/r/e9c191ae3f41bedc8ffd5c0fbcc5a1cec1d1d2df.1478120869.git.joe@perches.com Signed-off-by: Joe Perches Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/checkpatch.pl | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index 0c20f035ed99..cf95d3ae0754 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -3440,6 +3440,18 @@ sub process { #ignore lines not being added next if ($line =~ /^[^\+]/); +# check for dereferences that span multiple lines + if ($prevline =~ /^\+.*$Lval\s*(?:\.|->)\s*$/ && + $line =~ /^\+\s*(?!\#\s*(?!define\s+|if))\s*$Lval/) { + $prevline =~ /($Lval\s*(?:\.|->))\s*$/; + my $ref = $1; + $line =~ /^.\s*($Lval)/; + $ref .= $1; + $ref =~ s/\s//g; + WARN("MULTILINE_DEREFERENCE", + "Avoid multiple line dereference - prefer '$ref'\n" . $hereprev); + } + # check for declarations of signed or unsigned without int while ($line =~ m{\b($Declare)\s*(?!char\b|short\b|int\b|long\b)\s*($Ident)?\s*[=,;\[\)\(]}g) { my $type = $1;