[libcxx-commits] [libcxx] [libcxx][test-support] Implement fancy_pointer_allocator (PR #196187)

[Louis Dionne via libcxx-commits]

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@@ -393,21 +394,30 @@ namespace detail {
 template <class T>
 class thread_unsafe_shared_ptr {
 public:
-  thread_unsafe_shared_ptr() = default;
-
-  TEST_CONSTEXPR_CXX14 thread_unsafe_shared_ptr(const thread_unsafe_shared_ptr& other) : block(other.block) {
+  // as it's internal and technically not nullable, we don't care about null pointer state
+  // and don't need destructive move
+  TEST_CONSTEXPR_CXX14 thread_unsafe_shared_ptr(const thread_unsafe_shared_ptr& other) TEST_NOEXCEPT
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ldionne wrote:

Can you explain why these changes are needed? I don't quite understand the relationship these changes have with the introduction of the fancy pointer allocator.

https://github.com/llvm/llvm-project/pull/196187