配置脚本中CFLAGS处理的最佳实践？

I'm not a fan of autoconf, but in the interest of principle of least surprise, I'm trying to make my (non-autoconf) configure scripts behave as closely as possible to what users expect from an autoconf-based build system. The GNU coding standards are actually rather reasonable on this topic, and explicitly mention the possibility of not using autoconf/automake but providing a compatible interface in another way:I'm not a fan of autoconf, but in the interest