在Linux下一会看到cc,另一会又看到gcc,感觉又点混乱的样子。它们是同一个东西么,有啥区别呢
一分为二地看:
首先,如果讨论范围在Unix和Linux之间,那么cc和gcc不是同一个东西。cc来自于Unix的c语言编译器,是 c compiler 的缩写。gcc来自Linux世界,是GNU compiler collection 的缩写,注意这是一个编译器集合,不仅仅是c或c++。
其次, 如果讨论范围仅限于Linux,我们可以认为它们是一样的,在Linux下调用cc时,其实际上并不指向unix的cc编译器,而是指向了gcc,也就是说cc是gcc的一个链接(快捷方式),看看下面的终端输出就明白了:
1[root@andrew objs]# which cc 2/usr/bin/cc 3[root@andrew objs]# ls -al /usr/bin/cc 4lrwxrwxrwx. 1 root root 3 Nov 23 2015 /usr/bin/cc -> gcc
为什么会这样,很简单,为了兼容性:
cc是Unix下的,是收费的,可不向Linux那样可以那来随便用,所以Linux下是没有cc的
然后,问题来了,如果我的c/c++项目是在Unix下编写的,在写makefile文件时自然地用了cc,当将其放到Linux下这无法make了,必须将其中的cc全部修改成gcc。这太麻烦了哈,所以,Linux这想了这么一个方便的解决方案:不修改makefile,继续使用cc,这个cc是个“冒牌货”,它实际指向gcc。
注释:
1GCC, the GNU Compiler Collection 2 3 4The GNU Compiler Collection includes front ends for C, C++, Objective-C, Fortran, Ada, and Go, as well as libraries for these languages (libstdc++,...). GCC was originally written as the compiler for the GNU operating system. The GNU system was developed to be 100% free software, free in the sense that it respects the user's freedom. 5 6We strive to provide regular, high quality releases, which we want to work well on a variety of native and cross targets (including GNU/Linux), and encourage everyone to contribute changes or help testing GCC. Our sources are readily and freely available via SVN and weekly snapshots. 7 8Major decisions about GCC are made by the steering committee, guided by the mission statement.