fix c atomic test

Author: huixie90

clang/test/CodeGen/c11atomics-ios.c

@@ -235,6 +235,7 @@ _Bool test_promoted_cmpxchg(_Atomic(PS) *addr, PS *desired, PS *new) {
   // CHECK:   [[ATOMIC_DESIRED:%.*]] = alloca { %struct.PS, [2 x i8] }, align 8
   // CHECK:   [[ATOMIC_NEW:%.*]] = alloca { %struct.PS, [2 x i8] }, align 8
   // CHECK:   [[RES_ADDR:%.*]] = alloca i8, align 1
+  // CHECK:   [[OLD_TMP:%.*]] = alloca i64, align 8
   // CHECK:   store ptr %addr, ptr [[ADDR_ARG]], align 4
   // CHECK:   store ptr %desired, ptr [[DESIRED_ARG]], align 4
   // CHECK:   store ptr %new, ptr [[NEW_ARG]], align 4
@@ -251,7 +252,8 @@ _Bool test_promoted_cmpxchg(_Atomic(PS) *addr, PS *desired, PS *new) {
   // CHECK:   [[RES_BOOL:%.*]] = extractvalue { i64, i1 } [[RES]], 1
   // CHECK:   br i1 [[RES_BOOL]], label {{%.*}}, label {{%.*}}
 
-  // CHECK:   store i64 [[RES_VAL64]], ptr [[ATOMIC_DESIRED]], align 8
+  // CHECK:   store i64 [[RES_VAL64]], ptr [[OLD_TMP]], align 8
+  // CHECK:   call void @llvm.memcpy.p0.p0.i64(ptr align 2 [[DESIRED_ARG:%.*]], ptr align 8 [[OLD_TMP]], i64 6, i1 false)
   // CHECK:   br label {{%.*}}
 
   // CHECK:   [[RES_BOOL8:%.*]] = zext i1 [[RES_BOOL]] to i8

libcxx/test/std/atomics/atomics.types.generic/30023.pass.cpp

@@ -10,6 +10,7 @@
 // compare exchange does not work with types of which the size is not a power of 2
 
 // XFAIL: clang-20, clang-21, apple-clang-15, apple-clang-16, apple-clang-17
+// UNSUPPORTED: c++03
 
 #include <atomic>
 #include <cstring>