v3.0.12 build error on RHEL6

[A.L.M.Buxey at lboro.ac.uk]

Hi,

> This might be an easier (and more quick way) way than bootstrapping a
> modern GCC including dependencies properly on your own. I stumbled upon
> SCL some time ago unrelated to FreeRADIUS. The version of GCC shipped
> with EL6 is really becoming outdated to build for modern software on it.

+ - install devtoolset - version 6 i believe is the current, so

yum install devtoolset-6 

then add the required source line to your profile, or run the required
command before going to the FR source and doing the ./configure etc steps.

alan