Check the errorcode.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125804 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/Mutex.cpp b/lib/Support/Mutex.cpp
index 488868f..b408973 100644
--- a/lib/Support/Mutex.cpp
+++ b/lib/Support/Mutex.cpp
@@ -78,6 +78,7 @@
 #if !defined(__FreeBSD__) && !defined(__OpenBSD__) && !defined(__NetBSD__) && !defined(__DragonFly__)
     // Make it a process local mutex
     errorcode = pthread_mutexattr_setpshared(&attr, PTHREAD_PROCESS_PRIVATE);
+    assert(errorcode == 0);
 #endif
 
     // Initialize the mutex