Re: [PATCH] Fix web/60933

[Richard Biener <rguenther at suse dot de>]

On Thu, 24 Apr 2014, Eric Botcazou wrote:

> > Meanwhile is does the patch look ok?
> 
> No, the current wording is just fine and yours doesn't bring anything (even 
> the contrary, since you're listing known problematic versions).  This will 
> also break http://gcc.gnu.org/install/specific.html#sparc-x-x

Ah, I didn't see that.  So the issue here is that the host compiler
miscompiles the in-tree copy?  Maybe we should compile host libraries with
-O0 during stage1 (and require recent host GCC for compiling
cross compilers - which we probably do anyway).

It's an issue anyway as soon as we bump the versions downloaded
by contrib/download_prerequesites.  What "newer" versions are
affected, btw?  Are "very newer" versions fixed maybe?

> I don't see why we should special case GMP, MPFR and MPC here, look at all the 
> other dependencies on http://gcc.gnu.org/install/prerequisites.html
> 
> And IIUC the real issue is that ftp://gcc.gnu.org/pub/gcc/infrastructure/ 
> contains obsolete versions.

Hmm, ok.  Is the piece referencing contrib/download_prerequesites
and documenting that as the recommended way to setup and do
in-tree builds?

Generally we have conflicting goals - we want to make sure
GCC works with system supplied versions of the libraries
(thus the configure version checks), and we want to specify
versions that work for the in-tree builds (because of the
somewhat awkward setup of the build because of their inter-dependencies
and not doing intermediate installs).

-- 
Richard Biener <rguenther@suse.de>
SUSE / SUSE Labs
SUSE LINUX Products GmbH - Nuernberg - AG Nuernberg - HRB 16746
GF: Jeff Hawn, Jennifer Guild, Felix Imend"orffer