Just update the line in FIRFirestoreSettings.mm file (I have not updated any pods) From ABSL_CONST_INIT extern "C" const int64_t kFIRFirestoreCacheSizeUnlimited = Settings::CacheSizeUnlimited; To extern "C" const int64_t kFIRFirestoreCacheSizeUnlimited = Settings::CacheSizeUnlimited;