In file included from conftest.c:28:
/usr/include/libmemcachedprotocol-0.0/handler.h:20:18: error: conflicting types for 'ssize_t'; have 'long int'
   20 | typedef long int ssize_t;
      |                  ^~~~~~~
In file included from /usr/include/libmemcachedprotocol-0.0/handler.h:18,
                 from conftest.c:28:
/usr/include/sys/types.h:108:19: note: previous declaration of 'ssize_t' with type 'ssize_t' {aka 'int'}
  108 | typedef __ssize_t ssize_t;
      |                   ^~~~~~~
conftest.c: In function 'main':
conftest.c:32:39: warning: variable 's_test_impl' set but not used [-Wunused-but-set-variable]
   32 | memcached_binary_protocol_callback_st s_test_impl;

```      |                                       ^~~~~~~~~~~


Diag:  `HAVE_SSIZE_T` is only defined in `libmemcached-1.0/configure.h`