Fix unused variable warnings in atomic tests

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@242625 91177308-0d34-0410-b5e6-96231b3b80d8

test/std/atomics/atomics.flag/default.pass.cpp

@@ -22,7 +22,8 @@
 int main()
 {
     std::atomic_flag f;
-
+    f.clear();
+    assert(f.test_and_set() == 0);
     {
         typedef std::atomic_flag A;
         _ALIGNAS_TYPE(A) char storage[sizeof(A)] = {1};

test/std/atomics/atomics.types.generic/address.pass.cpp

@@ -81,12 +81,13 @@ do_test()
 {
     typedef typename std::remove_pointer<T>::type X;
     A obj(T(0));
+    bool b0 = obj.is_lock_free();
+    ((void)b0); // mark as unused
     assert(obj == T(0));
     std::atomic_init(&obj, T(1));
     assert(obj == T(1));
     std::atomic_init(&obj, T(2));
     assert(obj == T(2));
-    bool b0 = obj.is_lock_free();
     obj.store(T(0));
     assert(obj == T(0));
     obj.store(T(1), std::memory_order_release);

test/std/atomics/atomics.types.generic/bool.pass.cpp

@@ -60,7 +60,6 @@
 int main()
 {
     {
-        volatile std::atomic<bool> _;
         volatile std::atomic<bool> obj(true);
         assert(obj == true);
         std::atomic_init(&obj, false);
@@ -116,7 +115,6 @@ int main()
         assert(obj == true);
     }
     {
-        std::atomic<bool> _;
         std::atomic<bool> obj(true);
         assert(obj == true);
         std::atomic_init(&obj, false);
@@ -172,7 +170,6 @@ int main()
         assert(obj == true);
     }
     {
-        std::atomic_bool _;
         std::atomic_bool obj(true);
         assert(obj == true);
         std::atomic_init(&obj, false);

test/std/atomics/atomics.types.generic/integral.pass.cpp

@@ -103,6 +103,7 @@ do_test()
     std::atomic_init(&obj, T(2));
     assert(obj == T(2));
     bool b0 = obj.is_lock_free();
+    ((void)b0); // mark as unused
     obj.store(T(0));
     assert(obj == T(0));
     obj.store(T(1), std::memory_order_release);

test/std/atomics/atomics.types.operations/atomics.types.operations.req/atomic_is_lock_free.pass.cpp

@@ -20,6 +20,7 @@
 //     atomic_is_lock_free(const atomic<T>* obj);
 
 #include <atomic>
+#include <cassert>
 
 template <class T>
 void
@@ -30,6 +31,7 @@ test()
     bool b1 = std::atomic_is_lock_free(static_cast<const A*>(&t));
     volatile A vt;
     bool b2 = std::atomic_is_lock_free(static_cast<const volatile A*>(&vt));
+    assert(b1 == b2);
 }
 
 struct A