详解arm-elf与arm-linux的区别

以下是这两种交叉编译环境的区别

这两种交叉环境都使用过

在基于ARM的嵌入式系统开发中，常常用到交叉编译的GCC工具链有两种：arm-linux-*和 arm-elf-*，两者区别主要在于使用不同的C库文件。arm-linux-*使用GNU的Glibc，而arm-elf-*一般使用 uClibc/uC-libc或者使用RedHat专门为嵌入式系统的开发的C库newlib.Glibc。uClibc/uC-libc以及 newlib都是C语言库文件，只是所应用的领域不同而已，Glibc是针对PC开发的，uClibc/uC-libc是与Glibc API兼容的小型化C语言库，实现了Glibc部分功能。

关于uClibc/uC-libc的说明，详见如下：

There are two libc libraries commonly used with uClinux. uC-libc and uClibc. They are quite different despite their similar names. Here is a quick overview of how they are different.

uC-libc is the original library for uClinux. It was based on sources from the Linux-8086 C library which was part of the ELKs project with m68000 support added by Jeff Dionne and Kenneth Albanowski. It is a fairly complete libc implementation, however, some of the API"s are a little non-standard and quite a few common libc routines are not present. Currently it has stable support for m68000, ColdFire and ARM （Non-MMU） architectures. It was primary design goal is to be small and light weight. It does try to conform to any standards, although its API tries to be compatible with most libcs, it is not always exactly the same.

The uClinux distribution provides an environment that can compile using either uC-libc or uClibc depending on your needs. For m68000 and Coldfire platforms it is generally better to chose uC-libc as it supports shared libraries and is the most commonly used libc for these CPUs. uClibc also works quite well with almost all platforms supported by the distribution. Which libc you choose to use will be decided by your requirements

uClinux有两个经常使用的libc库：uC-libc和uClibc。虽然两者名字很相似，其实有差别，下面就简单的介绍一下二者的不同之处。uC -libc是最早为uClinux开发的库，是Jeff Dionne和Kenneth Albanowski为在EKLs项目中支持m68000在Linux-8086 C库源码上移植的。uC-libc是一个完全的libc实现，但其中有一些api是非标准的，有些libc的标准也没有实现。uC-libc稳定地支持 m68000，ColdFire和没有MMU的ARM。其主要设计目标是“小”、"轻"，并尽量与标准一致，虽然它的API和很多libc兼容，但是似乎并不像它期望的那样和所有标准一致。