checkpatch: avoid multiple line dereferences
Code that puts a single dereferencing identifier on multiple lines like:
struct_identifier->member[index].
member = <foo>;
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 <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 0c20f03..cf95d3a 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -3440,6 +3440,18 @@
#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;