执行make命令报错：/bin/sh: cc: command not found
原因：是因为系统缺少gcc环境，导致编译出错。
解决办法：安装gcc环境 yum install gcc-c++
继续执行make命令报错
参考官方文档：
Selecting a non-default memory allocator when building Redis is done by setting
the `MALLOC` environment variable. Redis is compiled and linked against libc
malloc by default, with the exception of jemalloc being the default on Linux
systems. This default was picked because jemalloc has proven to have fewer
fragmentation problems than libc malloc.
To force compiling against libc malloc, use:
% make MALLOC=libc
To compile against jemalloc on Mac OS X systems, use:
% make MALLOC=jemalloc
大致意思就是说redis编译的时候如果指定了MALLOC环境变量，那么redis在编译过程中lib就与这个MALLOC环境变量挂钩，如果没有指定就会用默认的jemalloc，之所以用它是因为它在解决碎片化问题比libc更好，系统没有jemalloc就会报错。
解决方案1：安装jemalloc
解决方案2：make MALLOC=libc