Temporary header file '/tmp/SsK6N4s5LV/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/planarity/appconst.h"
  #include "/usr/include/planarity/graph.h"
  #include "/usr/include/planarity/graphDrawPlanar.h"
  #include "/usr/include/planarity/graphDrawPlanar.private.h"
  #include "/usr/include/planarity/graphExtensions.h"
  #include "/usr/include/planarity/graphExtensions.private.h"
  #include "/usr/include/planarity/graphFunctionTable.h"
  #include "/usr/include/planarity/graphK23Search.h"
  #include "/usr/include/planarity/graphK23Search.private.h"
  #include "/usr/include/planarity/graphK33Search.h"
  #include "/usr/include/planarity/graphK33Search.private.h"
  #include "/usr/include/planarity/graphK4Search.h"
  #include "/usr/include/planarity/graphK4Search.private.h"
  #include "/usr/include/planarity/graphStructures.h"
  #include "/usr/include/planarity/listcoll.h"
  #include "/usr/include/planarity/planarity.h"
  #include "/usr/include/planarity/platformTime.h"
  #include "/usr/include/planarity/stack.h"
  #include "/usr/include/planarity/strbuf.h"

  // 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;

The GCC parameters:
  gcc -fdump-lang-raw -fkeep-inline-functions -c -x c++ -fpermissive -w "/tmp/SsK6N4s5LV/dump1.h"

In file included from /usr/include/planarity/graphStructures.h:17,
                 from /usr/include/planarity/graph.h:14,
                 from /tmp/SsK6N4s5LV/dump1.h:13:
/usr/include/planarity/graphExtensions.private.h:26:3: error: conflicting declaration ‘typedef struct graphExtension graphExtension’
   26 | } graphExtension;
      |   ^~~~~~~~~~~~~~
/usr/include/planarity/graphExtensions.private.h:25:12: note: previous declaration as ‘struct graphExtension’
   25 |     struct graphExtension *next;
      |            ^~~~~~~~~~~~~~