checkpatch: improve "return is not a function" test

Find a few more cases where parentheses are used around the value of a
return statement.

This now uses the "$balanced_parens" test and also makes the test depend
on perl v5.10 and higher.

This now finds return with parenthesis uses the old code did not find
like:

ERROR: return is not a function, parentheses are not required
#211: FILE: arch/m68k/include/asm/sun3xflop.h:211:
+		return ((error == 0) ? 0 : -1);

Signed-off-by: Joe Perches <joe@perches.com>
Tested-by: David Cohen <david.a.cohen@linux.intel.com>
Acked-by: David Cohen <david.a.cohen@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 14 deletions

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index ec9bbf863d50..6e0f1ec0d6f2 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -3233,21 +3233,10 @@ sub process {
                 }
 
 # Return is not a function.
-                if (defined($stat) && $stat =~ /^.\s*return(\s*)(\(.*);/s) {
+                if (defined($stat) && $stat =~ /^.\s*return(\s*)\(/s) {
                         my $spacing = $1;
-                        my $value = $2;
-
-                        # Flatten any parentheses
-                        $value =~ s/\(/ \(/g;
-                        $value =~ s/\)/\) /g;
-                        while ($value =~ s/\[[^\[\]]*\]/1/ ||
-                               $value !~ /(?:$Ident|-?$Constant)\s*
-                                             $Compare\s*
-                                             (?:$Ident|-?$Constant)/x &&
-                               $value =~ s/\([^\(\)]*\)/1/) {
-                        }
-#print "value<$value>\n";
-                        if ($value =~ /^\s*(?:$Ident|-?$Constant)\s*$/) {
+                        if ($^V && $^V ge 5.10.0 &&
+                            $stat =~ /^.\s*return\s*$balanced_parens\s*;\s*$/) {
                                 ERROR("RETURN_PARENTHESES",
                                       "return is not a function, parentheses are not required\n" . $herecurr);
 
@@ -3256,6 +3245,7 @@ sub process {
                                       "space required before the open parenthesis '('\n" . $herecurr);
                         }
                 }
+
 # Return of what appears to be an errno should normally be -'ve
                 if ($line =~ /^.\s*return\s*(E[A-Z]*)\s*;/) {
                         my $name = $1;