diff --git a/clang/test/SemaCXX/constexpr-builtin-bit-cast.cpp b/clang/test/SemaCXX/constexpr-builtin-bit-cast.cpp
--- a/clang/test/SemaCXX/constexpr-builtin-bit-cast.cpp
+++ b/clang/test/SemaCXX/constexpr-builtin-bit-cast.cpp
@@ -391,9 +391,11 @@
 };
 constexpr IdentityInStruct identity2a = {42};
 constexpr unsigned char identity2b = __builtin_bit_cast(unsigned char, identity2a.n);
+static_assert(identity2b == 42);
 
 union IdentityInUnion {
   unsigned char n;
 };
 constexpr IdentityInUnion identity3a = {42};
 constexpr unsigned char identity3b = __builtin_bit_cast(unsigned char, identity3a.n);
+static_assert(identity3b == 42);