[PATCH] checkpatch: don't match against empty $const_structs

[Jerome Forissier]

When $conststructsfile does not exist or is empty, we may get false
warnings such as:
WARNING: struct  should normally be const

Fix that by not running the string match if $const_structs is empty.

Signed-off-by: Jerome Forissier <jerome.forissier@xxxxxxxxxx>
---
 scripts/checkpatch.pl | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index a8368d1..722a319 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -6010,7 +6010,8 @@ sub process {
 		}
 
 # check for various structs that are normally const (ops, kgdb, device_tree)
-		if ($line !~ /\bconst\b/ &&
+		if ($const_structs ne "" &&
+		    $line !~ /\bconst\b/ &&
 		    $line =~ /\bstruct\s+($const_structs)\b/) {
 			WARN("CONST_STRUCT",
 			     "struct $1 should normally be const\n" .
-- 
2.7.4