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:
[root@andrew objs]# which cc
/usr/bin/cc
[root@andrew objs]# ls -al /usr/bin/cc
lrwxrwxrwx. 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:
GCC, the GNU Compiler Collection
The 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.
We 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.
Major decisions about GCC are made by the steering committee, guided by the mission statement.