Whom to send bugreport?

[Hans <hans.ullrich@loop.de>]

Dear ladies and gentlemen,

guess there is the following problem:

There is a third-party module for a kernel, which has to be compiled for the 
kernel.  This build is working fine!

After upgrading to a newer version of the kernel and of course newer kernel-
headers, the build is failing now with a crash. As the third-party module was 
not changed, the failure depends on some changes in the kernel-header files.

Whom the bugreport hast to be sent? The kernel-header maintainers? The third-
party? 

Whom has it to be sent, when a build fails with an official module delivered 
by the debian repo?

General question: When a build is failing on some files after an upgrade AND 
before the upgrade the build worked fine AND the sources where not changed, 
who is to contact then? The maintainers of the compiler? The maintainers of 
some libdevels?

In the past, it was not always be sure, who one has to contact, and sometimes 
no one seem to be responsible somehow.

Happy hacking and best regards

Hans