Author: Stephan T. Lavavej Date: 2023-11-27T17:19:34-08:00 New Revision: 7cbf9598cc6f207a268599cea636533a5c7b2dbd
URL: https://github.com/llvm/llvm-project/commit/7cbf9598cc6f207a268599cea636533a5c7b2dbd DIFF: https://github.com/llvm/llvm-project/commit/7cbf9598cc6f207a268599cea636533a5c7b2dbd.diff LOG: [libc++][test] Avoid using `allocator<const T>` (#73545) Found while running libc++'s test suite with MSVC's STL. MSVC's STL rejects `allocator<const T>`. This may or may not be justified by the current Standardese (it was bogus in the C++03 era), but it's how we reject usage like `vector<const T>`. A bunch of `mdspan` tests are failing for us because some centralized machinery is using `allocator<const T>`. Testing that `mdspan` and its associated types work properly with `const T` is good and necessary, but directly allocating `const T` is what's a problem for MSVC's STL. I'd like to ask for a very targeted change here that preserves all of the test coverage but changes how `ElementPool` interacts with `allocator`. This intentionally leaves `ElementPool::get_ptr()` returning `T*` (pointer-to-possibly-const), so there's no externally visible difference. Added: Modified: libcxx/test/std/containers/views/mdspan/MinimalElementType.h Removed: ################################################################################ diff --git a/libcxx/test/std/containers/views/mdspan/MinimalElementType.h b/libcxx/test/std/containers/views/mdspan/MinimalElementType.h index b1fbd6ed944d179..fe7f0e1f2383790 100644 --- a/libcxx/test/std/containers/views/mdspan/MinimalElementType.h +++ b/libcxx/test/std/containers/views/mdspan/MinimalElementType.h @@ -9,7 +9,8 @@ #ifndef TEST_STD_CONTAINERS_VIEWS_MDSPAN_MINIMAL_ELEMENT_TYPE_H #define TEST_STD_CONTAINERS_VIEWS_MDSPAN_MINIMAL_ELEMENT_TYPE_H -#include<memory> +#include <memory> +#include <type_traits> // Idiosyncratic element type for mdspan // Make sure we don't assume copyable, default constructible, movable etc. @@ -25,7 +26,7 @@ struct MinimalElementType { template<class T, size_t N> struct ElementPool { constexpr ElementPool() { - ptr_ = std::allocator<T>().allocate(N); + ptr_ = std::allocator<std::remove_const_t<T>>().allocate(N); for (int i = 0; i != N; ++i) std::construct_at(ptr_ + i, 42); } @@ -35,11 +36,11 @@ struct ElementPool { constexpr ~ElementPool() { for (int i = 0; i != N; ++i) std::destroy_at(ptr_ + i); - std::allocator<T>().deallocate(ptr_, N); + std::allocator<std::remove_const_t<T>>().deallocate(ptr_, N); } private: - T* ptr_; + std::remove_const_t<T>* ptr_; }; #endif // TEST_STD_CONTAINERS_VIEWS_MDSPAN_MINIMAL_ELEMENT_TYPE_H _______________________________________________ llvm-branch-commits mailing list llvm-branch-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
