checkpatch: handle do without braces if we have enough context

If we have sufficient context detect and handle do without braces ({).
Else these incorrectly trigger a trailing statements error for the
associated while.

Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 24 insertions, 3 deletions

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 17e1d94fa1fa..19690a2ddb74 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -1051,6 +1051,7 @@ sub process {
 
         # suppression flags
         my %suppress_ifbraces;
+        my %suppress_whiletrailers;
 
         # Pre-scan the patch sanitizing the lines.
         # Pre-scan the patch looking for any __setup documentation.
@@ -1156,6 +1157,7 @@ sub process {
                         $prev_values = 'E';
 
                         %suppress_ifbraces = ();
+                        %suppress_whiletrailers = ();
                         next;
 
 # track the line number as we move through the hunk, note that
@@ -1301,9 +1303,9 @@ sub process {
                 }
 
 # Check for potential 'bare' types
-                my ($stat, $cond, $line_nr_next, $remain_next);
+                my ($stat, $cond, $line_nr_next, $remain_next, $off_next);
                 if ($realcnt && $line =~ /.\s*\S/) {
-                        ($stat, $cond, $line_nr_next, $remain_next) =
+                        ($stat, $cond, $line_nr_next, $remain_next, $off_next) =
                                 ctx_statement_block($linenr, $realcnt, 0);
                         $stat =~ s/\n./\n /g;
                         $cond =~ s/\n./\n /g;
@@ -1952,7 +1954,26 @@ sub process {
 
 # Check for illegal assignment in if conditional -- and check for trailing
 # statements after the conditional.
-                if ($line =~ /\b(?:if|while|for)\s*\(/ && $line !~ /^.\s*#/) {
+                if ($line =~ /do\s*(?!{)/) {
+                        my ($stat_next) = ctx_statement_block($line_nr_next,
+                                                $remain_next, $off_next);
+                        $stat_next =~ s/\n./\n /g;
+                        ##print "stat<$stat> stat_next<$stat_next>\n";
+
+                        if ($stat_next =~ /^\s*while\b/) {
+                                # If the statement carries leading newlines,
+                                # then count those as offsets.
+                                my ($whitespace) =
+                                        ($stat_next =~ /^((?:\s*\n[+-])*\s*)/s);
+                                my $offset =
+                                        statement_rawlines($whitespace) - 1;
+
+                                $suppress_whiletrailers{$line_nr_next +
+                                                                $offset} = 1;
+                        }
+                }
+                if (!defined $suppress_whiletrailers{$linenr} &&
+                    $line =~ /\b(?:if|while|for)\s*\(/ && $line !~ /^.\s*#/) {
                         my ($s, $c) = ($stat, $cond);
 
                         if ($c =~ /\bif\s*\(.*[^<>!=]=[^=].*/) {