工程在不小心删除了一个链接库的情况下，突然出现了下面错误：
Undefined symbols for architecture i386:
"_u_errorName", referenced from:
_rkl_NSExceptionForRegex in libPods.a(RegexKitLite.o)
_rkl_makeNSError in libPods.a(RegexKitLite.o)
_rkl_userInfoDictionary in libPods.a(RegexKitLite.o)
"_u_strlen", referenced from:
_rkl_userInfoDictionary in libPods.a(RegexKitLite.o)
"_uregex_appendReplacement", referenced from:
_rkl_replaceAll in libPods.a(RegexKitLite.o)
"_uregex_appendTail", referenced from:
_rkl_replaceAll in libPods.a(RegexKitLite.o)
"_uregex_clone", referenced from:
-[RKLBlockEnumerationHelper initWithRegex:options:string:range:error:] in libPods.a(RegexKitLite.o)
"_uregex_close", referenced from:
_rkl_clearCachedRegex in libPods.a(RegexKitLite.o)
"_uregex_end", referenced from:
_rkl_performRegexOp in libPods.a(RegexKitLite.o)
_rkl_findRanges in libPods.a(RegexKitLite.o)
_rkl_search in libPods.a(RegexKitLite.o)
"_uregex_find", referenced from:
_rkl_search in libPods.a(RegexKitLite.o)
"_uregex_findNext", referenced from:
_rkl_search in libPods.a(RegexKitLite.o)
_rkl_replaceAll in libPods.a(RegexKitLite.o)
"_uregex_groupCount", referenced from:
_rkl_getCachedRegex in libPods.a(RegexKitLite.o)
"_uregex_open", referenced from:
_rkl_getCachedRegex in libPods.a(RegexKitLite.o)
"_uregex_reset", referenced from:
_rkl_replaceAll in libPods.a(RegexKitLite.o)
"_uregex_setText", referenced from:
-[RKLBlockEnumerationHelper initWithRegex:options:string:range:error:] in libPods.a(RegexKitLite.o)
_rkl_clearCachedRegexSetTo in libPods.a(RegexKitLite.o)
_rkl_setCachedRegexToString in libPods.a(RegexKitLite.o)
"_uregex_start", referenced from:
_rkl_performRegexOp in libPods.a(RegexKitLite.o)
_rkl_findRanges in libPods.a(RegexKitLite.o)
_rkl_search in libPods.a(RegexKitLite.o)
ld: symbol(s) not found for architecture i386
clang: error: linker command failed with exit code 1 (use -v to see invocation)
啊舒服的阿萨德阿萨德发阿萨德发阿萨德发
才发现是Other Linker Flags，缺少了licucore。
然后在Other Linker Flags后面，添加“-licucore”就可以了。