diff --git a/src/corelib/ipc/qsystemsemaphore_systemv.cpp b/src/corelib/ipc/qsystemsemaphore_systemv.cpp
index cdfa6adfd4..e976fa5e09 100644
--- a/src/corelib/ipc/qsystemsemaphore_systemv.cpp
+++ b/src/corelib/ipc/qsystemsemaphore_systemv.cpp
@@ -53,6 +53,9 @@ bool QSystemSemaphoreSystemV::runtimeSupportCheck()
  */
 key_t QSystemSemaphoreSystemV::handle(QSystemSemaphorePrivate *self, QSystemSemaphore::AccessMode mode)
 {
+    if (unix_key != -1)
+        return unix_key;  // we already have a semaphore
+
 #if defined(Q_OS_DARWIN)
     if (qt_apple_isSandboxed()) {
         // attempting to use System V semaphores will get us a SIGSYS
@@ -73,9 +76,6 @@ key_t QSystemSemaphoreSystemV::handle(QSystemSemaphorePrivate *self, QSystemSema
         return -1;
     }
 
-    if (-1 != unix_key)
-        return unix_key;
-
     // ftok requires that an actual file exists somewhere
     int built = QtIpcCommon::createUnixKeyFile(nativeKeyFile);
     if (-1 == built) {