[libcxx-commits] [PATCH] D110994: [libc++] Make test_allocator constexpr-friendly for constexpr string/vector

[Nikolas Klauser via Phabricator via libcxx-commits]

philnik added inline comments.


================
Comment at: libcxx/test/support/test_allocator.h:256-263
 #if TEST_STD_VER < 11
-    void construct(pointer p, const T& val)
-        {::new(static_cast<void*>(p)) T(val);}
+  void construct(pointer p, const T& val) { ::new (static_cast<void*>(p)) T(val); }
 #else
-    template <class U> void construct(pointer p, U&& val)
-        {::new(static_cast<void*>(p)) T(std::forward<U>(val));}
+  template <class U>
+  void construct(pointer p, U&& val) {
+    ::new (static_cast<void*>(p)) T(std::forward<U>(val));
+  }
----------------
ldionne wrote:
> Based on what I did in D68365, I think the correct definition of this would be:
> 
> ```
> #if TEST_STD_VER < 11
>     void construct(pointer p, const T& val) {
>         ::new(static_cast<void*>(p)) T(val);
>     }
> #elif TEST_STD_VER < 20
>     template <class U>
>     void construct(pointer p, U&& val) {
>         ::new(static_cast<void*>(p)) T(std::forward<U>(val));
>     }
> #else
>     template <class U>
>     constexpr void construct(pointer p, U&& val) {
>         std::construct_at(p, std::forward<U>(val));
>     }
> #endif
> ```
> 
I think it can just be removed, since it doesn't ever get used anyways and is removed in C++20 from ##std::allocator##.


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D110994/new/

https://reviews.llvm.org/D110994