nvidia-kernel-dkms fails to build nvidia driver with backport kernel

[John Coltrane]

Hello list,

hopefully this is the right place to post my problem.

My box runs mostly on wheezy, rarely with packages from wheezy-backports.

Normally kernel 3.2.0-4-amd64 from stable is used on my box, but I need
to have kernel linux-image-3.11-0.bpo.2-amd64 from backports.

There already is nvidia-* 304.88-1+deb7u1 on my box, accompanied by dkms
2.2.0.3-1.2 and nvidia-kernel-dkms 304.88-1+deb7u1. The headerfiles are
also installed:

ii linux-headers-3.11-0.bpo.2-all 3.11.10-1~bpo70+1 amd64 All header
files for Linux 3.11 (meta-package)
ii linux-headers-3.11-0.bpo.2-all-amd64 3.11.10-1~bpo70+1 amd64 All
header files for Linux 3.11 (meta-package)
ii linux-headers-3.11-0.bpo.2-amd64 3.11.10-1~bpo70+1 amd64 Header files
for Linux 3.11-0.bpo.2-amd64
ii linux-headers-3.11-0.bpo.2-common 3.11.10-1~bpo70+1 amd64 Common
header files for Linux 3.11-0.bpo.2

The headerfiles for 3.2.0-4-amd64 are also installed. With 3.2.0-4 all
is working well (nvidia related).

gcc is version 4.6.3 (Debian 4.6.3-14), both the stable and the
backports kernels are compiled with this version.

When nvidia-dkms tries to build the nvidia.ko kernelmodule for 3.11-0 it
fails, here are the last few lines (where an error comes up) from
/var/lib/dkms/nvidia/304.88/build/make.log:

/var/lib/dkms/nvidia/304.88/build/nv-i2c.c: In function
‘nv_i2c_del_adapter’:
/var/lib/dkms/nvidia/304.88/build/nv-i2c.c:327:14: error: void value not
ignored as it ought to be
make[4]: *** [/var/lib/dkms/nvidia/304.88/build/nv-i2c.o] Error 1
make[3]: *** [_module_/var/lib/dkms/nvidia/304.88/build] Error 2
make[2]: *** [sub-make] Error 2
make[1]: *** [all] Error 2
make[1]: Leaving directory `/usr/src/linux-headers-3.11-0.bpo.2-amd64'
make: *** [modules] Error 2
make: Leaving directory `/var/lib/dkms/nvidia/304.88/build'


What can I do ?

If you need more info please contact me.

Thanks in advance

-John