Temporary header file '/tmp/kJklnRnZNC/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/ffindex.h"
  #include "/usr/include/ffindex_posix_search.h"
  #include "/usr/include/ffutil.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;
  ffindex_db* tmp_add_class_3;
  ffindex_entry* tmp_add_class_4;
  ffindex_index* tmp_add_class_5;

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

In file included from /tmp/kJklnRnZNC/dump1.h:12:
/usr/include/ffindex.h: In function ‘size_t ffindex_max_index_entries()’:
/usr/include/ffindex.h:81:57: error: ‘getenv’ was not declared in this scope
   81 | inline size_t ffindex_max_index_entries(){ char *FMIE = getenv("FFINDEX_MAX_INDEX_ENTRIES"); if( FMIE ) { return atol( FMIE ); } else { return FFINDEX_MAX_INDEX_ENTRIES_DEFAULT; } }
      |                                                         ^~~~~~
/usr/include/ffindex.h:23:1: note: ‘getenv’ is defined in header ‘<cstdlib>’; did you forget to ‘#include <cstdlib>’?
   22 | #include <stdio.h>
  +++ |+#include <cstdlib>
   23 | 
/usr/include/ffindex.h:81:114: error: ‘atol’ was not declared in this scope
   81 | inline size_t ffindex_max_index_entries(){ char *FMIE = getenv("FFINDEX_MAX_INDEX_ENTRIES"); if( FMIE ) { return atol( FMIE ); } else { return FFINDEX_MAX_INDEX_ENTRIES_DEFAULT; } }
      |                                                                                                                  ^~~~