/Users/bjori/Source/phongo/php_phongo.c:493:17: warning: assigning to 'mongoc_write_concern_t *' (aka 'struct _mongoc_write_concern_t *') from 'const mongoc_write_concern_t *'
      (aka 'const struct _mongoc_write_concern_t *') discards qualifiers [-Wincompatible-pointer-types-discards-qualifiers]
                write_concern = mongoc_client_get_write_concern(client);
                              ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Users/bjori/Source/phongo/php_phongo.c:1069:47: warning: passing 'const char *' to parameter of type 'char *' discards qualifiers [-Wincompatible-pointer-types-discards-qualifiers]
                add_assoc_string_ex(retval, ZEND_STRS("w"), wtag, 1);
                                                            ^~~~
/usr/local/p/versions/5.6-dev/include/php/Zend/zend_API.h:384:82: note: passing argument to parameter 'str' here
ZEND_API int add_assoc_string_ex(zval *arg, const char *key, uint key_len, char *str, int duplicate);
                                                                                 ^
2 warnings generated.