Temporary header file '/tmp/0J72LfOjkN/dump1.h' with the following content will be compiled to create GCC translation unit dump:

  // add defines
  #define __STDC_VERSION__ 201710L
#define _TIME_BITS 64
#define _FILE_OFFSET_BITS 64
#define _GXX_NULLPTR_T
#define CLUTTER_ENABLE_COMPOSITOR_API 1
#define _REGEX_NELTS(n)
#define _Atomic
#define PACKED

  // add includes
  #include "/usr/include/sigc++-2.0/sigc++/adaptors/adaptor_trait.h"
  #include "/usr/include/sigc++-2.0/sigc++/adaptors/adaptors.h"
  #include "/usr/include/sigc++-2.0/sigc++/adaptors/bind.h"
  #include "/usr/include/sigc++-2.0/sigc++/adaptors/bind_return.h"
  #include "/usr/include/sigc++-2.0/sigc++/adaptors/bound_argument.h"
  #include "/usr/include/sigc++-2.0/sigc++/adaptors/compose.h"
  #include "/usr/include/sigc++-2.0/sigc++/adaptors/deduce_result_type.h"
  #include "/usr/include/sigc++-2.0/sigc++/adaptors/exception_catch.h"
  #include "/usr/include/sigc++-2.0/sigc++/adaptors/hide.h"
  #include "/usr/include/sigc++-2.0/sigc++/adaptors/lambda/base.h"
  #include "/usr/include/sigc++-2.0/sigc++/adaptors/lambda/select.h"
  #include "/usr/include/sigc++-2.0/sigc++/adaptors/retype.h"
  #include "/usr/include/sigc++-2.0/sigc++/adaptors/retype_return.h"
  #include "/usr/include/sigc++-2.0/sigc++/adaptors/track_obj.h"
  #include "/usr/include/sigc++-2.0/sigc++/bind.h"
  #include "/usr/include/sigc++-2.0/sigc++/bind_return.h"
  #include "/usr/include/sigc++-2.0/sigc++/connection.h"
  #include "/usr/include/sigc++-2.0/sigc++/functors/functor_trait.h"
  #include "/usr/include/sigc++-2.0/sigc++/functors/functors.h"
  #include "/usr/include/sigc++-2.0/sigc++/functors/mem_fun.h"
  #include "/usr/include/sigc++-2.0/sigc++/functors/ptr_fun.h"
  #include "/usr/include/sigc++-2.0/sigc++/functors/slot.h"
  #include "/usr/include/sigc++-2.0/sigc++/functors/slot_base.h"
  #include "/usr/include/sigc++-2.0/sigc++/limit_reference.h"
  #include "/usr/include/sigc++-2.0/sigc++/reference_wrapper.h"
  #include "/usr/include/sigc++-2.0/sigc++/retype_return.h"
  #include "/usr/include/sigc++-2.0/sigc++/sigc++.h"
  #include "/usr/include/sigc++-2.0/sigc++/signal.h"
  #include "/usr/include/sigc++-2.0/sigc++/signal_base.h"
  #include "/usr/include/sigc++-2.0/sigc++/slot.h"
  #include "/usr/include/sigc++-2.0/sigc++/trackable.h"
  #include "/usr/include/sigc++-2.0/sigc++/type_traits.h"
  #include "/usr/include/sigc++-2.0/sigc++/visit_each.h"
  #include "/usr/lib/arm-linux-gnueabihf/sigc++-2.0/include/sigc++config.h"

  // add namespaces
  namespace sigc{typedef int tmp_add_type_1;}
  sigc::tmp_add_type_1 tmp_add_func_1(){return 0;};
  namespace sigc{namespace internal{typedef int tmp_add_type_2;}}
  sigc::internal::tmp_add_type_2 tmp_add_func_2(){return 0;};

The GCC parameters:
  gcc -fdump-lang-raw -fkeep-inline-functions -c -x c++ -fpermissive -w "/tmp/0J72LfOjkN/dump1.h"  -I/usr/lib/arm-linux-gnueabihf/sigc\+\+-2.0/include -I/usr/include/sigc\+\+-2.0