Make python 2.7 the default python in centos, making an alias didn't work

Question

I am trying to install llvm on my centos 6.7. While running the configure file it says it throws the error

checking for python >= 2.7... not found configure: error: found python 2.6.6 (/usr/bin/python); required >= 2.7 See `config.log' for more details.

So I installed python 2.7, but since the previous python version is already in there the configure shows the same error. I tried aliasing python with the new python version using

alias python=/usr/local/bin/python2.7

This made python2.7 to be executed while calling python. But the error while running the configure file is still there. How can I resolve this.

Solution

If you want Python 2.7 on a CentOS6 system, install the Python 2.7 Software Collection package. It will not replace /usr/bin/python, but if you load the python27 scl, configure will detect it.

Note: you should just use the EPEL package for llvm if that's all you want.

Comments

[vonbrand]

llvm (i.e.. clang and friends) are available in EPEL. No need to compile by hand.

[Rakesh R Nair]

@darklion build python from the source. yum wont install python to the latest version

[gardenhead]

Download a more recent version of Python and then change your Path or PythonPath to point to that.

[jsbillings]

This will break your CentOS system. If you replace /usr/bin/python with something you built in /usr/local, your system will never be able to run 'yum' and you will cease to get any software updates and security fixes.