Bug#908568: nvidia-driver: build error

[Vincent Lefevre]

Control: retitle -1 nvidia kernel modules build error on GCC version mismatch

On 2018-09-11 09:54:06 -0700, Russ Allbery wrote:
> Vincent Lefevre <vincent at vinc17.net> writes:
> 
> > Even with just a differing *minor* version? Note that since GCC 5,
> > an update of the minor version should just be bug fixes:
> 
> >   https://gcc.gnu.org/develop.html
> 
> The kernel uses GCC-specific features in an extremely aggressive way.  I'm
> not particularly surprised that ABI compatibility might break across minor
> versions.  Normally the linux-compiler-gcc-* packages express the required
> compiler version for building kernel modules and handle this, but they're
> only an upgrade ratchet, not a downgrade ratchet.  (Plus, that would just
> create an unsatisfiable dependency since the compiler packages aren't
> broken apart that way.)

This would mean that a breakage is possible after any patch
(in particular with those "Update to SVN..." in the changelog).
Thus this means that the kernel module build system must check
that the GCC Debian package version number matches the one used
to build the kernel. For sid, GCC is often not in sync with the
one used to build the kernel. This is a really big problem.

-- 
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