diff --git a/src/server/master.cc b/src/server/master.cc
index 0090c845adb..ed9068f8a9d 100644
--- a/src/server/master.cc
+++ b/src/server/master.cc
@@ -1735,6 +1735,10 @@ static void swServer_signal_handler(int sig)
     swTraceLog(SW_TRACE_SERVER, "signal[%d] %s triggered in %d", sig, swSignal_str(sig), getpid());
 
     swServer *serv = SwooleG.serv;
+    if (!SwooleG.running or !serv) {
+        return;
+    }
+
     int status;
     pid_t pid;
     switch (sig)
diff --git a/tests/include/lib/src/DbWrapper.php b/tests/include/lib/src/DbWrapper.php
index 8309875b937..1a2c6c16f4a 100644
--- a/tests/include/lib/src/DbWrapper.php
+++ b/tests/include/lib/src/DbWrapper.php
@@ -2,6 +2,7 @@
 
 namespace SwooleTest;
 
+use RuntimeException;
 use Swoole\Coroutine\MySQL;
 
 class DbWrapper
diff --git a/tests/include/lib/src/ProcessManager.php b/tests/include/lib/src/ProcessManager.php
index 00315f3cbef..4d2a50d036f 100644
--- a/tests/include/lib/src/ProcessManager.php
+++ b/tests/include/lib/src/ProcessManager.php
@@ -249,7 +249,7 @@ public function run($redirectStdout = false)
         $waitInfo = Swoole\Process::wait(true);
         $this->childStatus = $waitInfo['code'];
         if (!in_array($waitInfo['signal'], $this->expectExitSignal)) {
-            throw new RuntimeException("Unexpected exit code {$waitInfo['signal']}");
+            throw new \RuntimeException("Unexpected exit code {$waitInfo['signal']}");
         }
 
         return true;