In file included from main.cpp:28:0:
fixed_allocator.h: In instantiation of 'FixedAllocator<Tp>::FixedAllocator(uint64_t) [with Tp = int; uint64_t = long unsigned int]':
main.cpp:44:32:   required from here
fixed_allocator.h:35:29: error: 'FixedAllocator<int>::page_size' will be initialized after [-Werror=reorder]
     std::uint64_t page_size{};
                             ^
fixed_allocator.h:7:19: error:   'PageAllocator FixedAllocator<int>::page_allocator_' [-Werror=reorder]
     PageAllocator page_allocator_;
                   ^~~~~~~~~~~~~~~
fixed_allocator.h:10:14: error:   when initialized here [-Werror=reorder]
     explicit FixedAllocator(std::uint64_t page_size)
              ^~~~~~~~~~~~~~
fixed_allocator.h: In instantiation of 'FixedAllocator<Tp>::FixedAllocator(uint64_t) [with Tp = std::__cxx11::basic_string<char>; uint64_t = long unsigned int]':
main.cpp:55:41:   required from here
fixed_allocator.h:35:29: error: 'FixedAllocator<std::__cxx11::basic_string<char> >::page_size' will be initialized after [-Werror=reorder]
     std::uint64_t page_size{};
                             ^
fixed_allocator.h:7:19: error:   'PageAllocator FixedAllocator<std::__cxx11::basic_string<char> >::page_allocator_' [-Werror=reorder]
     PageAllocator page_allocator_;
                   ^~~~~~~~~~~~~~~
fixed_allocator.h:10:14: error:   when initialized here [-Werror=reorder]
     explicit FixedAllocator(std::uint64_t page_size)
              ^~~~~~~~~~~~~~
fixed_allocator.h: In instantiation of 'FixedAllocator<Tp>::FixedAllocator(uint64_t) [with Tp = char; uint64_t = long unsigned int]':
main.cpp:116:35:   required from here
fixed_allocator.h:35:29: error: 'FixedAllocator<char>::page_size' will be initialized after [-Werror=reorder]
     std::uint64_t page_size{};
                             ^
fixed_allocator.h:7:19: error:   'PageAllocator FixedAllocator<char>::page_allocator_' [-Werror=reorder]
     PageAllocator page_allocator_;
                   ^~~~~~~~~~~~~~~
fixed_allocator.h:10:14: error:   when initialized here [-Werror=reorder]
     explicit FixedAllocator(std::uint64_t page_size)
              ^~~~~~~~~~~~~~
cc1plus: all warnings being treated as errors