[CMake] How to build CMake so it works on an older Linux?

[Alexander Neundorf]

On 2018 M04 5, Thu 21:24:40 CEST Alexander Neundorf wrote:
> On 2018 M04 5, Thu 16:15:17 CEST suzuki toshiya wrote:
> > Dear Eric,
> > 
> > # if anybody think "how C++11 environment should be prepared
> > # on legacy GNU/Linux" is off-topic and should be discussed
> > # in off-list, please let me know. I will do so.
> > 
> > Eric Wing wrote:
> > > Thanks for the responses. Yes, I just need this to run on Ubuntu 12.04
> > > (and some other old Linux's in that era). Yes, I think the probably is
> > > the libstdc++ dependency.
> > > 
> > > As pointed out, it is really hard to get a newer compiler on Ubuntu
> > > 12.04. I've been down this road before, and if memory serves, the gcc
> > > bootstrapping process to get a newer compiler doesn't seem to work
> > > with a compiler older than gcc 4.8. Same goes for clang, which also
> > > weirdly relies on gcc 4.8 to bootstrap itself.
> > 
> > At least, gcc-4.6.3, the last official gcc for Ubuntu-12.04, could
> > build gcc-4.8.5 manually (without shared libstdc++, so confused
> > dependency could be avoided). And, I could build cmake-3.11.0 by it.
> > Now I'm checking "make test".
> 
> I have recently built a gcc 4.9.5 on Centos 5, i.e. gcc 4.1. There were no
> issues after getting the configure flags right.

4.9.4 I mean.
You can see the flags here:
https://hub.docker.com/r/aneundorf/docker-centos5-build-svn-gcc/~/dockerfile/
(but the docker image didn't build, it was killed by a dockerhub timeout).

Alex