1 files changed, 40 insertions, 0 deletions
diff --git a/tests/spin3.c b/tests/spin3.c
new file mode 100644
index 0000000..8b383de
--- /dev/null
+++ b/tests/spin3.c
@@ -0,0 +1,40 @@
+/* 
+ * spin3.c
+ *
+ * Thread A locks spin - thread B tries to unlock.
+ * This should succeed, but it's undefined behaviour.
+ *
+ */
+
+#include "test.h"
+
+static int wasHere = 0;
+
+static pthread_spinlock_t spin;
+ 
+void * unlocker(void * arg)
+{
+  int expectedResult = (int) arg;
+
+  wasHere++;
+  assert(pthread_spin_unlock(&spin) == expectedResult);
+  wasHere++;
+  return NULL;
+}
+ 
+int
+main()
+{
+  pthread_t t;
+  pthread_spinattr_t ma;
+
+  wasHere = 0;
+  assert(pthread_spin_init(&spin, PTHREAD_PROCESS_PRIVATE) == 0);
+  assert(pthread_spin_lock(&spin) == 0);
+  assert(pthread_create(&t, NULL, unlocker, (void *) 0) == 0);
+  assert(pthread_join(t, NULL) == 0);
+  assert(pthread_spin_unlock(&spin) == EPERM);
+  assert(wasHere == 2);
+
+  return 0;
+}