Added test for atomic ivars.

Test/CMakeLists.txt

@@ -40,6 +40,7 @@ set(TESTS
 	WeakReferences_arc.m
 	WeakImportClass.m
 	ivar_arc.m
+	ivar_atomic.m
 	IVarOverlap.m
 	IVarSuperclassOverlap.m
 	objc_msgSend.m

Test/ivar_atomic.m

@@ -0,0 +1,24 @@
+#include "Test.h"
+
+#import <stdatomic.h>
+
+@interface Dummy : Test
+{
+	atomic_bool atomicBool;
+}
+@end
+
+@implementation Dummy
+- (void)test
+{
+  int value = 1;
+  object_setIvar(self, class_getInstanceVariable(object_getClass(self), "atomicBool"), (__bridge id)(void*)(intptr_t)value);
+}
+@end
+
+
+int main(int argc, char *argv[])
+{
+	[[Dummy new] test];
+	return 0;
+}