In file included from main.cpp:28:0:
fixed_allocator.h: In instantiation of 'Tp* FixedAllocator<Tp>::Allocate() [with Tp = int]':
main.cpp:45:30:   required from here
fixed_allocator.h:19:39: error: invalid conversion from 'void*' to 'int*' [-fpermissive]
       return page_allocator_->Allocate();
              ~~~~~~~~~~~~~~~~~~~~~~~~~^~
fixed_allocator.h: In instantiation of 'Tp* FixedAllocator<Tp>::Allocate() [with Tp = std::__cxx11::basic_string<char>]':
main.cpp:57:24:   required from here
fixed_allocator.h:19:39: error: invalid conversion from 'void*' to 'std::__cxx11::basic_string<char>*' [-fpermissive]
fixed_allocator.h: In instantiation of 'Tp* FixedAllocator<Tp>::Allocate() [with Tp = char]':
main.cpp:119:40:   required from here
fixed_allocator.h:19:39: error: invalid conversion from 'void*' to 'char*' [-fpermissive]