libmemcached 編譯錯誤

今天在一台主機上編譯 memcached 的用戶端庫 libmemcached，./configure 配置結果如下

---

Configuration summary for libmemcached version 0.40

   * Installation prefix:       /usr/local

   * System type:               pc-linux-gnu

   * Host CPU:                  i686

   * C Compiler:                gcc (GCC) 4.1.2 20080704 (Red Hat 4.1.2-46)

   * Assertions enabled:        yes

   * Debug enabled:             no

   * Warnings as failure:       no

---

在運作編譯後，出現如下錯誤

clients/ms_conn.o: In function `ms_get_udp_request_id':

/root/libmemcached-0.40/clients/ms_conn.c:194: undefined reference to `__sync_fetch_and_add_4'

clients/ms_conn.o: In function `ms_reconn_socks':

/root/libmemcached-0.40/clients/ms_conn.c:1051: undefined reference to `__sync_fetch_and_add_4'

clients/ms_conn.o: In function `ms_reconn':

/root/libmemcached-0.40/clients/ms_conn.c:919: undefined reference to `__sync_fetch_and_add_4'

/root/libmemcached-0.40/clients/ms_conn.c:956: undefined reference to `__sync_fetch_and_add_4'

clients/ms_thread.o: In function `ms_setup_thread':

/root/libmemcached-0.40/clients/ms_thread.c:225: undefined reference to `__sync_fetch_and_add_4'

clients/ms_thread.o:/root/libmemcached-0.40/clients/ms_thread.c:208: more undefined references to `__sync_fetch_and_add_4' follow

collect2: ld returned 1 exit status

估計是伺服器 i386 和 i686 的關系，Google 後通過配置指令解決

./configure --disable-64bit CFLAGS="-O3 -march=i686"