Checking for self assign

to avoid potential UB if doing memcpy of buffer to itself

dynarray.h

@@ -113,12 +113,8 @@ class dynarray
 	dynarray & operator =(dynarray && other) &
 		noexcept(_alloTrait::propagate_on_container_move_assignment::value or _alloTrait::is_always_equal::value);
 	//! Requires that allocator_type is always equal or does not have propagate_on_container_copy_assignment
-	dynarray & operator =(const dynarray & other) &
-		{
-			static_assert(!_alloTrait::propagate_on_container_copy_assignment::value or _alloTrait::is_always_equal::value,
-			              "Alloc propagate_on_container_copy_assignment unsupported");
-			assign(other);  return *this;
-		}
+	dynarray & operator =(const dynarray & other) &;
+
 	dynarray & operator =(std::initializer_list<T> il) &  { assign(il);  return *this; }
 
 	void        swap(dynarray & other) noexcept;
@@ -479,7 +475,6 @@ class dynarray
 			else
 			{	_m.end = _m.data + count;
 			}
-			// UB for self assign, but found to work. Add check in operator = or use memmove?
 			_detail::MemcpyCheck(src, count, _m.data);
 
 			return src + count;
@@ -771,6 +766,17 @@ dynarray<T, Alloc> &  dynarray<T, Alloc>::operator =(dynarray && other) &
 	return *this;
 }
 
+template< typename T, typename Alloc >
+dynarray<T, Alloc> &  dynarray<T, Alloc>::operator =(const dynarray & other) &
+{
+	static_assert(!_alloTrait::propagate_on_container_copy_assignment::value or _alloTrait::is_always_equal::value,
+	              "Alloc propagate_on_container_copy_assignment unsupported");
+	if (this != &other) // avoid memcpy data to itself
+		assign(other);
+
+	return *this;
+}
+
 template< typename T, typename Alloc >
 dynarray<T, Alloc>::dynarray(size_type n, for_overwrite_t, Alloc a)
  :	_m(a)