Bug#1023690: gcc-11 should not be shipped in bookworm

[Helmut Grohne <helmut@subdivi.de>]

Hi Matthias,

On Mon, Sep 01, 2025 at 07:49:51AM +0200, Matthias Klose wrote:
> it's too early for the first solution.  We still need 11 for bootstrapping
> libgphobos on ppc64el, and we need to address the issue about a "stable"
> compiler for shim.

I was not aware of the ppc64el aspect and expecting the shim part. Do 
note that opinions on the bootstrapping aspect vary. In theory, we'd 
need every major version of rustc to bootstrap rustc as each of them 
requires the previous one. Yet, that's not what we're doing. We'd also 
need gcc-4.0 in principle as that could be built without a C++ compiler. 
There may be other compromises here, but implementing them may not be 
worth the effort.

How about deleting gcc-11 and gcc-12 based cross toolchains but keeping 
the native ones then? Do we need either of those cross toolchains for 
the aforementioned use cases? Removing them without also removing gcc-11 
and gcc-12 would be sufficient to make most of the undeclared file 
conflicts go away.

Helmut