[libcxx-commits] [libcxx] [libc++] Flat containers should reject `vector<bool, Alloc>` (PR #224886)

[Nikolas Klauser via libcxx-commits]

================
@@ -89,8 +89,10 @@ class flat_map {
                 "The stored elements' key type must match the underlying key container's value_type.");
   static_assert(is_same_v<_Tp, typename _MappedContainer::value_type>,
                 "The stored elements' mapped type must match the underlying mapped container's value_type.");
-  static_assert(!is_same_v<_KeyContainer, std::vector<bool>>, "vector<bool> is not a sequence container");
-  static_assert(!is_same_v<_MappedContainer, std::vector<bool>>, "vector<bool> is not a sequence container");
+  static_assert(!__is_std_vector_bool_v<_KeyContainer>,
+                "The underlying key container must not be std::vector<bool>, which is not a sequence container.");
----------------
philnik777 wrote:

```suggestion
  static_assert(!__is_std_vector_bool_v<_KeyContainer>,
                "The underlying key container must not be std::vector<bool> because it is not a sequence container.");
```

https://github.com/llvm/llvm-project/pull/224886