bitbake: runqueue: Don't error if we never setup workers

If we didn't setup any workers (such as bitbake -S), this would error
since we're trying to set a signal handler to None. This patch
avoids that problem.

(Bitbake rev: ce17478c8197abf178c00774f5bbe23fd4375ee2)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 2 insertions, 1 deletions

diff --git a/bitbake/lib/bb/runqueue.py b/bitbake/lib/bb/runqueue.py
index a30f594e44..3c72b60f50 100644
--- a/bitbake/lib/bb/runqueue.py
+++ b/bitbake/lib/bb/runqueue.py
@@ -947,7 +947,8 @@ class RunQueue:
 
     def teardown_workers(self):
         self.teardown = True
-        signal.signal(signal.SIGCHLD, self.oldsigchld)
+        if self.oldsigchld:
+            signal.signal(signal.SIGCHLD, self.oldsigchld)
         self._teardown_worker(self.worker, self.workerpipe)
         self.worker = None
         self.workerpipe = None