Temporary header file '/tmp/EXotAsPIqG/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/share/cargo/registry/onig_sys-69.8.0/oniguruma/src/oniggnu.h"
  #include "/usr/share/cargo/registry/onig_sys-69.8.0/oniguruma/src/onigposix.h"
  #include "/usr/share/cargo/registry/onig_sys-69.8.0/oniguruma/src/oniguruma.h"
  #include "/usr/share/cargo/registry/onig_sys-69.8.0/oniguruma/src/regenc.h"
  #include "/usr/share/cargo/registry/onig_sys-69.8.0/oniguruma/src/regint.h"
  #include "/usr/share/cargo/registry/onig_sys-69.8.0/oniguruma/src/regparse.h"
  #include "/usr/share/cargo/registry/onig_sys-69.8.0/oniguruma/src/st.h"
  #include "/usr/share/cargo/registry/onig_sys-69.8.0/oniguruma/tis-ci/config.h"

  // add classes
  ByUnfoldKey* tmp_add_class_0;
  OnigCaptureTreeNodeStruct* tmp_add_class_1;
  OnigEncodingTypeST* tmp_add_class_2;
  PropertyNameCtype* tmp_add_class_3;
  _BBuf* tmp_add_class_4;
  _Node* tmp_add_class_5;
  re_pattern_buffer* tmp_add_class_6;
  re_registers* tmp_add_class_7;
  st_hash_type* tmp_add_class_8;
  st_table* tmp_add_class_9;

The GCC parameters:
  gcc -fdump-lang-raw -fkeep-inline-functions -c -x c++ -fpermissive -w "/tmp/EXotAsPIqG/dump1.h"  -I/usr/share/cargo/registry/onig_sys-69.8.0/oniguruma/tis-ci

In file included from /tmp/EXotAsPIqG/dump1.h:16:
/usr/share/cargo/registry/onig_sys-69.8.0/oniguruma/src/regint.h:605:13: error: conflicting declaration ‘typedef int SaveType’
  605 | typedef int SaveType;
      |             ^~~~~~~~
/usr/share/cargo/registry/onig_sys-69.8.0/oniguruma/src/regint.h:573:6: note: previous declaration as ‘enum SaveType’
  573 | enum SaveType {
      |      ^~~~~~~~
/usr/share/cargo/registry/onig_sys-69.8.0/oniguruma/src/regint.h:606:13: error: conflicting declaration ‘typedef int UpdateVarType’
  606 | typedef int UpdateVarType;
      |             ^~~~~~~~~~~~~
/usr/share/cargo/registry/onig_sys-69.8.0/oniguruma/src/regint.h:579:6: note: previous declaration as ‘enum UpdateVarType’
  579 | enum UpdateVarType {
      |      ^~~~~~~~~~~~~
/usr/share/cargo/registry/onig_sys-69.8.0/oniguruma/src/regint.h:762:11: error: expected unqualified-id before ‘not’ token
  762 |       int not;
      |           ^~~
In file included from /tmp/EXotAsPIqG/dump1.h:17:
/usr/share/cargo/registry/onig_sys-69.8.0/oniguruma/src/regparse.h:222:7: error: expected unqualified-id before ‘not’ token
  222 |   int not;
      |       ^~~