diff --git a/src/client/linux/crash_generation/crash_generation_server.cc b/src/client/linux/crash_generation/crash_generation_server.cc
index 1d7d93b9..26c50a5c 100644
--- a/src/client/linux/crash_generation/crash_generation_server.cc
+++ b/src/client/linux/crash_generation/crash_generation_server.cc
@@ -255,7 +255,7 @@ CrashGenerationServer::ClientEvent(short revents)
   }
 
   if (crashing_pid == -1 || signal_fd == -1) {
-    if (signal_fd)
+    if (signal_fd != -1)
       close(signal_fd);
     return true;
   }