diff --git a/iocore/net/AsyncSignalEventIO.h b/iocore/net/AsyncSignalEventIO.h
index 4786df30dc2..515b0c1933d 100644
--- a/iocore/net/AsyncSignalEventIO.h
+++ b/iocore/net/AsyncSignalEventIO.h
@@ -35,5 +35,5 @@ class AsyncSignalEventIO : public EventIO
   void process_event(int flags) override;
 
 private:
-  int _fd;
+  int _fd = -1;
 };