Re: building GCC - please check method, and results so far over multiple platforms

[Paul Smith <paul at mad-scientist dot net>]

On Mon, 2017-04-10 at 11:41 +0200, Toebs Douglass wrote:
> > It won't use the latest and greatest version of mpfr etc for each
> > compiler release, but it'll use the version that most builds of that
> > release were built with, and keep you out of the weeds covering rarely
> > trodden paths.
> 
> Hmm.  That is interesting.  Is it then that GCC builds *normally* use
> the oldest possible working version of the dependency libraries?

The official GCC builds, and all distribution builds that I'm aware of,
use the versions specified by that script.  In fact, the very newest
versions of these libraries often don't work with GCC (put another way,
GCC has not been updated to work with the newest versions of these
libraries).

I believe that GCC has used the same versions of these libraries at
least from 4.9.x through 6.x (the latest I've tried).

I can't speak to whether or not they are missing out on improvements or
not, but if you're trying to duplicate the GCC that everyone is using
then you want to run the download_prerequisites script; it's definitely
maintained.

In fact this is what both https://gcc.gnu.org/install/index.html and
https://gcc.gnu.org/wiki/InstallingGCC recommend.