Temporary header file '/tmp/JarsSejFYA/dump1.h' with the following content will be compiled to create GCC translation unit dump:

  // add defines
  #define __STDC_VERSION__ 201710L
#define _GXX_NULLPTR_T
#define CLUTTER_ENABLE_COMPOSITOR_API 1
#define _REGEX_NELTS(n)
#define _Atomic
#define PACKED
#define getaddrinfo_a(a,b,c,d)

  // add includes
  #include "/usr/include/mmap_access_mode.h"
  #include "/usr/include/mmap_allocator.h"
  #include "/usr/include/mmap_exception.h"
  #include "/usr/include/mmap_file_pool.h"
  #include "/usr/include/mmappable_vector.h"

  // add namespaces
  namespace mmap_allocator_namespace{typedef int tmp_add_type_1;}
  mmap_allocator_namespace::tmp_add_type_1 tmp_add_func_1(){return 0;};

  // add classes
  _G_fpos64_t* tmp_add_class_0;
  _G_fpos_t* tmp_add_class_1;
  _IO_cookie_io_functions_t* tmp_add_class_2;
  statx_timestamp* tmp_add_class_3;

The GCC parameters:
  gcc -fdump-lang-raw -fkeep-inline-functions -c -x c++ -fpermissive -w "/tmp/JarsSejFYA/dump1.h"

In file included from /tmp/JarsSejFYA/dump1.h:15:
/usr/include/mmap_file_pool.h:9:15: error: redefinition of ‘class mmap_allocator_namespace::mmap_file_identifier’
    9 |         class mmap_file_identifier {
      |               ^~~~~~~~~~~~~~~~~~~~
In file included from /usr/include/mmap_allocator.h:10,
                 from /tmp/JarsSejFYA/dump1.h:13:
/usr/include/mmap_file_pool.h:9:15: note: previous definition of ‘class mmap_allocator_namespace::mmap_file_identifier’
    9 |         class mmap_file_identifier {
      |               ^~~~~~~~~~~~~~~~~~~~
/usr/include/mmap_file_pool.h:24:15: error: redefinition of ‘class mmap_allocator_namespace::mmapped_file’
   24 |         class mmapped_file {
      |               ^~~~~~~~~~~~
/usr/include/mmap_file_pool.h:24:15: note: previous definition of ‘class mmap_allocator_namespace::mmapped_file’
   24 |         class mmapped_file {
      |               ^~~~~~~~~~~~
/usr/include/mmap_file_pool.h:56:15: error: redefinition of ‘class mmap_allocator_namespace::mmap_file_pool’
   56 |         class mmap_file_pool {
      |               ^~~~~~~~~~~~~~
/usr/include/mmap_file_pool.h:56:15: note: previous definition of ‘class mmap_allocator_namespace::mmap_file_pool’
   56 |         class mmap_file_pool {
      |               ^~~~~~~~~~~~~~