scripts/lib/kdoc/kdoc_files.py: don't try to join None

If out_msg() returns None, it means that an unknown declaration
was found. Avoid letting the script crash on such case.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/4334d16f14cfd93e611b290fb56c35d236cadcb7.1744685912.git.mchehab+huawei@kernel.org

diff --git a/scripts/lib/kdoc/kdoc_files.py b/scripts/lib/kdoc/kdoc_files.py
index dd003feefd1bf899a2da6a370dcb24adc4d7dfe1..2e51e5f3bb77f66668ef07c3c5f10b2354212ce3 100644 (file)
--- a/scripts/lib/kdoc/kdoc_files.py
+++ b/scripts/lib/kdoc/kdoc_files.py
@@ -270,13 +270,16 @@ class KernelFiles():
 
             msg = ""
             for name, arg in self.results[fname]:
-                msg += self.out_msg(fname, name, arg)
+                m = self.out_msg(fname, name, arg)
 
-                if msg is None:
+                if m is None:
                     ln = arg.get("ln", 0)
                     dtype = arg.get('type', "")
 
                     self.config.log.warning("%s:%d Can't handle %s",
                                             fname, ln, dtype)
+                else:
+                    msg += m
+
             if msg:
                 yield fname, msg