Temporary header file '/tmp/2iUCnKICVT/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/stdint.h"
  #include "/usr/include/wyhash/o1hash.h"
  #include "/usr/include/wyhash/wyhash.h"
  #include "/usr/include/wyhash/wyhash32.h"

The GCC parameters:
  gcc -fdump-lang-raw -fkeep-inline-functions -c -x c++ -fpermissive -w "/tmp/2iUCnKICVT/dump1.h"

In file included from /tmp/2iUCnKICVT/dump1.h:13:
/usr/include/wyhash/o1hash.h: In function ‘unsigned int _o1r4(const uint8_t*)’:
/usr/include/wyhash/o1hash.h:16:73: error: ‘memcpy’ was not declared in this scope
   16 | static inline unsigned _o1r4(const uint8_t *p) {        unsigned v;     memcpy(&v, p, 4);       return v;}
      |                                                                         ^~~~~~
/usr/include/wyhash/o1hash.h:1:1: note: ‘memcpy’ is defined in header ‘<cstring>’; did you forget to ‘#include <cstring>’?
  +++ |+#include <cstring>
    1 | /*
/usr/include/wyhash/o1hash.h: At global scope:
/usr/include/wyhash/o1hash.h:24:48: error: ‘size_t’ has not been declared
   24 | static inline uint64_t o1hash(const void *key, size_t len) {
      |                                                ^~~~~~
In file included from /tmp/2iUCnKICVT/dump1.h:15:
/usr/include/wyhash/wyhash32.h:24:24: error: redefinition of ‘uint64_t wyrand(uint64_t*)’
   24 | static inline uint64_t wyrand(uint64_t *seed){
      |                        ^~~~~~
In file included from /tmp/2iUCnKICVT/dump1.h:14:
/usr/include/wyhash/wyhash.h:121:24: note: ‘uint64_t wyrand(uint64_t*)’ previously defined here
  121 | static inline uint64_t wyrand(uint64_t *seed){  *seed+=_wyp[0]; return _wymix(*seed,*seed^_wyp[1]);}
      |                        ^~~~~~