Removed xtrivially_default_constructible (#2903)

Author: JohanMabille

include/xtensor/containers/xbuffer_adaptor.hpp

@@ -709,7 +709,7 @@ namespace xt
                     rhs.get_allocator()
                 );
                 pointer tmp = safe_init_allocate(al, rhs.m_size);
-                if (xtrivially_default_constructible<value_type>::value)
+                if (std::is_trivially_default_constructible<value_type>::value)
                 {
                     std::uninitialized_copy(rhs.m_data.get(), rhs.m_data.get() + rhs.m_size, tmp);
                 }

include/xtensor/containers/xstorage.hpp

@@ -167,7 +167,7 @@ namespace xt
             using pointer = typename traits::pointer;
             using value_type = typename traits::value_type;
             pointer res = alloc.allocate(size);
-            if (!xtrivially_default_constructible<value_type>::value)
+            if (!std::is_trivially_default_constructible<value_type>::value)
             {
                 for (pointer p = res; p != res + size; ++p)
                 {
@@ -189,7 +189,7 @@ namespace xt
             using value_type = typename traits::value_type;
             if (ptr != nullptr)
             {
-                if (!xtrivially_default_constructible<value_type>::value)
+                if (!std::is_trivially_default_constructible<value_type>::value)
                 {
                     for (pointer p = ptr; p != ptr + size; ++p)
                     {
@@ -325,7 +325,7 @@ namespace xt
                 rhs.get_allocator()
             );
             resize_impl(rhs.size());
-            if (xtrivially_default_constructible<value_type>::value)
+            if (std::is_trivially_default_constructible<value_type>::value)
             {
                 std::uninitialized_copy(rhs.p_begin, rhs.p_end, p_begin);
             }
@@ -1255,7 +1255,7 @@ namespace xt
     template <class T, std::size_t N, class A, bool Init>
     inline void svector<T, N, A, Init>::destroy_range(T* begin, T* end)
     {
-        if (!xtrivially_default_constructible<T>::value)
+        if (!std::is_trivially_default_constructible<T>::value)
         {
             while (begin != end)
             {

include/xtensor/utils/xutils.hpp

@@ -609,34 +609,6 @@ namespace xt
     template <typename E>
     concept iterator_concept = is_iterator<E>::value;
 
-    /********************************************
-     * xtrivial_default_construct implemenation *
-     ********************************************/
-
-#if defined(_GLIBCXX_RELEASE) && _GLIBCXX_RELEASE >= 7
-// has_trivial_default_constructor has not been available since libstdc++-7.
-#define XTENSOR_GLIBCXX_USE_CXX11_ABI 1
-#else
-#if defined(_GLIBCXX_USE_CXX11_ABI)
-#if _GLIBCXX_USE_CXX11_ABI || (defined(_GLIBCXX_USE_DUAL_ABI) && !_GLIBCXX_USE_DUAL_ABI)
-#define XTENSOR_GLIBCXX_USE_CXX11_ABI 1
-#endif
-#endif
-#endif
-
-#if !defined(__GNUG__) || defined(_LIBCPP_VERSION) || defined(XTENSOR_GLIBCXX_USE_CXX11_ABI)
-
-    template <class T>
-    using xtrivially_default_constructible = std::is_trivially_default_constructible<T>;
-
-#else
-
-    template <class T>
-    using xtrivially_default_constructible = std::has_trivial_default_constructor<T>;
-
-#endif
-#undef XTENSOR_GLIBCXX_USE_CXX11_ABI
-
     /*************************
      * conditional type cast *
      *************************/