diff --git a/libcxx/include/__config b/libcxx/include/__config
--- a/libcxx/include/__config
+++ b/libcxx/include/__config
@@ -1055,6 +1055,12 @@
 #  define _LIBCPP_CONSTEXPR_AFTER_CXX17
 #endif
 
+#if _LIBCPP_STD_VER > 17 && defined(__cpp_constexpr_dynamic_alloc) && (__cpp_constexpr_dynamic_alloc >= 201907L)
+#  define _LIBCPP_CONSTEXPR_DESTRUCTOR constexpr
+#else
+#  define _LIBCPP_CONSTEXPR_DESTRUCTOR
+#endif
+
 // The _LIBCPP_NODISCARD_ATTRIBUTE should only be used to define other
 // NODISCARD macros to the correct attribute.
 #if __has_cpp_attribute(nodiscard) || defined(_LIBCPP_COMPILER_MSVC)
diff --git a/libcxx/include/optional b/libcxx/include/optional
--- a/libcxx/include/optional
+++ b/libcxx/include/optional
@@ -221,7 +221,7 @@
     bool __engaged_;
 
     _LIBCPP_INLINE_VISIBILITY
-    _LIBCPP_CONSTEXPR_AFTER_CXX17 ~__optional_destruct_base()
+    _LIBCPP_CONSTEXPR_DESTRUCTOR ~__optional_destruct_base()
     {
         if (__engaged_)
             __val_.~value_type();