#pragma GCC diagnostic push 和 #pragma GCC diagnostic pop
用途
#pragma GCC diagnostic push：用于记录当前的诊断状态
#pragma GCC diagnostic pop：用于恢复诊断状态
用法
#pragma GCC diagnostic push
#pragma GCC diagnostic [kind] "option"
/* code */
#pragma GCC diagnostic push
示例
#pragma GCC diagnostic ignored "option"：忽略option诊断信息；
#pragma GCC diagnostic error "option"：将Option诊断视为错误；
#pragma GCC error "message"：Generates an error message. This pragma is considered to indicate an error in the compilation, and it will be treated as such.